Grammar-Quizzes › Connectors › Subordinators › So that vs. So

So that vs. So

Express purpose vs. result

Purpose vs. Effect

SO THAT — PURPOSE
An action/plan may be followed by so that + a clause that expresses purpose or goal. The clause after so usually includes a modal, such as can, could, will, would, may or might, all of which express general timing. The time of the purpose is usually (but not always) later than the time when one makes the plan. A similar meaning can be expressed with in order + infinitive clause.
ACTION / PLAN	PURPOSE (SO THAT)
We decided to stay out all night	so that we could¹ watch a meteor storm. (connective preposition + that-clause)
We will take lots of blankets	so (that)³ we can keep ourselves warm.
ACTION / PLAN	PURPOSE (IN ORDER)
We took some blankets	in order to to keep ourselves warm.

SO — RESULT
An action or a situation may also be followed by so + a clause that expresses result (effect). A past tense cause-effect clause requires more precise timing. For this reason, (be) able is used instead of could when expressing ability. A somewhat similar meaning can be expressed with the intensifier so in the main clause followed by that + result clause.
SITUATION /CAUSE	RESULT / EFFECT (SO)
We stayed out all night,	so we were able² to see the meteor storm pass. (PP) (coordinator "result")
We have lots of blankets,	so we will be able to keep ourselves warm.
SITUATION / CAUSE (SO)	EFFECT / RESULT (THAT)
We had so many blankets (so–intensifier)	that we were able to keep ourselves warm all night. (that – subordinate marker)

(Aarts " Purpose, Result" 156) (Huddleston "Cause and Result" 726-7); (Huddleston "could/ able" 197)

¹could – expresses a time that is general, "timeless", anytime, whenever (i.e., "could" occurs in past and present/future contexts.) A similar timelessness is expressed by an infinitive clause in the another expression of purpose, in order → We stayed out (in order) to watch the sky.

²was/were able – expresses a time clearly pinned to the past. We stayed out, [so we were able to watch the sky]. (result or effect).

³ that – may be omitted in speech but not writing

so is often called a coordinator; however, it does not function (is not used) as other coordinators (and, but, or) are. See Coordinator Properties.

See "So" Uses below and Grammar Notes.

Related pages: Cause & Effect Overview, So that/Such that , "So" Uses, Pop-Q Resultive "so".

So that

Expressions for Purpose

So that vs. other expressions

SO THAT
So (that) is followed by a clause stating purpose or intent. The l that-clause often includes — can, could, may, might, etc.
ACTION TAKEN	PURPOSE
	THAT + MODAL
We take blankets	so that we can keep warm.
We took blankets	so (that) we could keep warm.
We take blankets	in order that we might keep warm.
We take blankets	that we may keep warm.

OTHER EXPRESSIONS
Other expressions, mostly prepositional phrases, are followed by gerund or infinitive clauses (nonfinite clause).
ACTION TAKEN	PURPOSE
	INFINITIVE CLAUSE
We take blankets	to keep warm.
	so as to keep warm.
	in order to keep warm.
	GERUND CLAUSE with a view to keeping warm.
	with the intent of keeping warm.
	for the purpose of keeping warm.
	NOUN PHRASE for warmth. (noun phrase)

keep warm (expression) – stay or remain warm; not become cold

PPs with clausal complements & NP complements (Huddleston 727)

Also see Stating Purpose (in order to).

So that

Expressions for Effect (Result)

So with clausal complements

SO THAT
So that is followed by a clause stating an effect for the action in the first clause. The clauses are separated by a comma. Including that is optional in speech.
ACTION TAKEN	EFFECT
We took blankets,	so (that) we weren't cold.
	so we weren't cold.

OTHER EXPRESSIONS
Other expressions (connective adverbs) join a second clause with an effect of the action in the first clause. The expressions below relate the meaning of effect (result).
ACTION TAKEN	EFFECT
We took blankets	As a result, we weren't cold.
	Consequently, we weren't cold.
	For this reason, we weren't cold.
	Therefore, we weren't cold.

keep warm (expression) – stay or remain warm; not become cold

See Cause-Effect, Because of / Despite

Also see Background "So".

So Punctuation

Expressing purpose vs effect

Punctuation

PURPOSE
When the meaning of so is purpose, use no comma. (So is a preposition complemented by that + clause.)
The baby pulled the lever so he could get some candy.

PURPOSE

no comma When the meaning of so is purpose, use no comma. (So is a preposition complemented by that + clause.)

baby reaching for gumball The baby pulled the lever so he could get some candy.

EFFECT
When the meaning of so is result, separate the clauses with a comma. (So is coordinates two clauses.)
The baby cried, so his mother gave him some candy.

EFFECT

comma When the meaning of so is result, separate the clauses with a comma. (So is coordinates two clauses.)

baby crying The baby cried, so his mother gave him some candy.

Also see: Stating Purpose FANBOYS (punctuation)

See Grammar Notes below for parts of speech.

"So" Uses

Express a variety of concepts

So and So!

SO	IN A SENTENCE
SO very	It's so cold today. I'm so glad to meet you. (very) [degree adverb]
SO this way	I want it so. (in this way) [pronoun]
SO also	He wants it and so do I. (in the same way) [paired coordinator] (and so, and too)
SO-SO eh	I'm feeling so-so today. (mediocre) [expression]
SO truly	I was so right there! (truly, indeed) [degree adverb modifier to a preposition]
SO approximately	Ten or so are here. (approximately) [noun]
SO! Got you	So! You took the last piece. (exclamation of shock or discovery) [discourse adverb]
SO AND SO cursed person	That so-and-so borrowed my car without asking! (replacement words for cursing someone; that SOB!) [expression]
SO end of conversation	So. (That's it. Nothing else. I don't have anything more to add.) [expression]

IN A SENTENCE

very

It's so cold today. I'm so glad to meet you. (very)

[degree adverb]

this way

I want it so. (in this way)

[pronoun]

also

He wants it and so do I. (in the same way)

[paired coordinator] (and so, and too)

SO-SO

I'm feeling so-so today. (mediocre)

[expression]

truly

I was so right there! (truly, indeed)

[degree adverb modifier to a preposition]

approximately

Ten or so are here. (approximately)

[noun]

SO!

Got you

So! You took the last piece. (exclamation of shock or discovery)

[discourse adverb]

SO AND SO

cursed person

That so-and-so borrowed my car without asking! (replacement words for cursing someone; that SOB!)

[expression]

end of conversation

So. (That's it. Nothing else. I don't have anything more to add.)

[expression]

SO	IN A SENTENCE
SO result	He left, so I left too. (effect – comma) [connective adverb]
SO THAT purpose	I left so that I could catch a bus. (purpose) [connective preposition]
SO…THAT cause-effect	It was so hot that the candles melted. (result) [degree adverb + that + resultative clause]
SO TO SPEAK figuratively	He was pulling my leg, so to speak. (figuratively speaking) [Speech-act adverb expression]
SO MANY/MUCH intensifier	We bought so many oranges. (quantity) We have so much juice. [degree adverb]
SO AS for the purpose of	We laughed so as to let them know our true thoughts. (for the purpose of) [prepositional phrase so that, in order]
SO WHAT of what consequence?	So what? (Who cares? (insignificant) or And what will happen? (consequence, next step) [connective adverb]
SO backgrounding	So originally we tried to make a prototype… (Answer filling in background information—circumstances leading up to the current focus) [discourse adverb]
SO I've wanted to ask.	So when did you first realize that you wanted to be an astronomer? (conversational opener; no comma)

IN A SENTENCE

result

He left, so I left too. (effect – comma)

[connective adverb]

SO THAT

purpose

I left so that I could catch a bus. (purpose)

[connective preposition]

SO…THAT

cause-effect

It was so hot that the candles melted. (result)

[degree adverb + that + resultative clause]

SO TO SPEAK

figuratively

He was pulling my leg, so to speak.

(figuratively speaking) [Speech-act adverb expression]

SO MANY/MUCH

intensifier

We bought so many oranges. (quantity) We have so much juice. [degree adverb]

SO AS

for the purpose of

We laughed so as to let them know our true thoughts. (for the purpose of)

[prepositional phrase so that, in order]

SO WHAT

of what consequence?

So what? (Who cares? (insignificant) or And what will happen? (consequence, next step)

[connective adverb]

backgrounding

So originally we tried to make a prototype…

(Answer filling in background information—circumstances leading up to the current focus) [discourse adverb]

I've wanted to ask.

So when did you first realize that you wanted to be an astronomer? (conversational opener; no comma)

Also see: so much / so many | Background "so" | Such Expressions.

Common Mistakes

Errors and Solutions

Error and Solution

ERROR
*He didn't give me his telephone number so I couldn't call him. (Unclear meaning)
He didn't give me his telephone number. So I looked it up. (Not incorrect, but not always acceptable)

ERROR

*He didn't give me his telephone number so I couldn't call him.

(Unclear meaning)

He didn't give me his telephone number. So I looked it up.

(Not incorrect, but not always acceptable)

SOLUTION
Was I unable to call him, or did he withhold his number? He didn't give me his telephone number, so I couldn't call him. (With a comma, it means "I was unable to call".) He didn't give me his telephone number so that I couldn't call him. (Without a comma, it means "He kept me from calling him by not giving me his number".)
This is a grammar dispute. Traditional grammar includes so with coordinators, which are placed between two equal structural elements, for example, two independent clauses. He didn't give me his number, so I looked it up. Similarly and and but, may not be preferred at the beginning of a sentence by some; however, there is no grammatical rule supporting this prohibition. See Beginning with And. Linguists analyze so as a Connective Adverb rather than a Coordinator . In this case, it is perfectly acceptable to begin a clause with so. So, I looked it up.

SOLUTION

Was I unable to call him, or did he withhold his number?
He didn't give me his telephone number, so I couldn't call him.
(With a comma, it means "I was unable to call".)

He didn't give me his telephone number so that I couldn't call him.
(Without a comma, it means "He kept me from calling him by not giving me his number".)

This is a grammar dispute.

Traditional grammar includes so with coordinators, which are placed between two equal structural elements, for example, two independent clauses. He didn't give me his number, so I looked it up.

Similarly and and but, may not be preferred at the beginning of a sentence by some; however, there is no grammatical rule supporting this prohibition. See Beginning with And.

Linguists analyze so as a Connective Adverb rather than a Coordinator . In this case, it is perfectly acceptable to begin a clause with so. So, I looked it up.

*Yellow highlighting marks examples of incorrect usage.

► Show Grammar Notes and Works Cited ▼ Hide Grammar Notes

Grammar Notes (Advanced)

Traditional Grammar and Linguistic Description

Traditional / ESL and Linguistic Descriptions

TRADITIONAL / ESL GRAMMAR
SO—PURPOSE No specific term is given for the so that (purpose) structure. The general term used in Chapter 19 is connective. A clause that can answer a "Why?" question is an adverbial. Why did you bring a blanket? I brought it so that we could keep warm. (Azar 19-5) In the (cause-effect) structure, so (adj / adv) that , the general term used in Chapter 19 is connective. No specific term is mentioned in 19-4. So is an adverb paired with a that-clause. Why did you need to bring a blanket? It was so cold that I had to bring a blanket. (Azar 19-4) So is also a coordinating conjunction that joins two independent clauses, and expresses an cause-effect relationship. I was cold, so I put on my coat. (Azar 19-2) that + clause — ("these structures" – term not mentioned) (Swan 543)

TRADITIONAL / ESL GRAMMAR

SO—PURPOSE

No specific term is given for the so that (purpose) structure. The general term used in Chapter 19 is connective. A clause that can answer a "Why?" question is an adverbial.
Why did you bring a blanket? I brought it so that we could keep warm. (Azar 19-5)

In the (cause-effect) structure, so (adj / adv) that , the general term used in Chapter 19 is connective. No specific term is mentioned in 19-4. So is an adverb paired with a that-clause.
Why did you need to bring a blanket? It was so cold that I had to bring a blanket. (Azar 19-4)

So is also a coordinating conjunction that joins two independent clauses, and expresses an cause-effect relationship. I was cold, so I put on my coat. (Azar 19-2)

that + clause

— ("these structures" – term not mentioned) (Swan 543)

LINGUISTIC DESCRIPTION
so + content clause so Adj / Adv adjunct.modifier in AdjP or AdvP (Aarts 64) degree adverb.modifier (Huddleston 6 §7.2, 11 §4.6) degree adverb.modifier (Swan 538.4) So occurs immediately before the content clause it licenses in constructions, involving manner, result, and purpose adjuncts.
that + clause subordinate marker + finite clause, content clause (Huddleston 11 §4.6, 11 §8.3) He set up his telescope so that it was pointed to the northern sky. [manner] He set up his telescope so that we were able to see the northern sky. [result] He set up his telescope so that we could see the northern sky. [purpose]

LINGUISTIC DESCRIPTION

so + content clause

so Adj / Adv

adjunct.modifier in AdjP or AdvP (Aarts 64)
degree adverb.modifier (Huddleston 6 §7.2, 11 §4.6)
degree adverb.modifier (Swan 538.4)

So occurs immediately before the content clause it licenses in constructions, involving manner, result, and purpose adjuncts.

that + clause

subordinate marker + finite clause, content clause (Huddleston 11 §4.6, 11 §8.3)

He set up his telescope so that it was pointed to the northern sky. [manner]
He set up his telescope so that we were able to see the northern sky. [result]
He set up his telescope so that we could see the northern sky. [purpose]

Works Cited

Aarts, Bas. Oxford Modern English Grammar. Oxford UP, 2011.
Azar, Betty Schrampfer, and Stacy A. Hagen. Understanding and Using English Grammar. 4th ed., Pearson Education, 2009.
Biber, Douglas, and Stig Johansson, et al. Longman Grammar Of Spoken And Written English. Pearson Education, 1999.
Huddleston, Rodney D., and Geoffrey K. Pullum. The Cambridge Grammar of the English Language. Cambridge UP, 2002.
Swan, Michael. Practical English Usage. 3rd ed., Oxford UP, 2005.

Practice1

Tracking Meteorites

Read the Context

Scientists are studying meteorites. Their intent is to understand the bio-origins of the meteorites. The scientists look carefully at the composition of meteorites. The purpose is to learn about comets, exploding stars and other phenomena. Astronomers track where fragments fall. They do this in order to recover them. Astronomers photograph the paths of meteors in the sky. This is for the purpose of estimating where the meteor pieces will land.

Astronomers have recovered several meteorites in this manner. As a result, they now have a large collection of meteorites. Peter Jenkins, a NASA astronomer, saw a meteor streak across the sky one afternoon.

Consequently, he and his team spent a week looking for the fragments. His team found nothing. Therefore, they made an announcement and asked the public (people) to help search for meteorites in their backyards. Soon a woman called reporting that she had found a large black, metallic rock that had bounced off her roof. For this reason, the team went and checked out "the rock". It was, indeed, a meteorite that had hit her roof. She took a picture of it as a souvenir and then gave the meteorite to the astronomers to allow them to study it. Later, the team returned it to the woman for that reason that she wanted her insurance company to cover (pay for) the damage to her roof.

astronomers (N) – scientists who study the cosmos (comets, planets, stars, etc.)
bio-origin – biological origin, composition, what they come from

comet (N) – a body moving about the sun, usually in a highly eccentric orbit, consisting of a central mass surrounded by an envelope of dust and gas that may form a tail that streams away from the sun

composition (N) – the combining of parts or elements to form a whole

estimate (V) – calculate, predict, an educated guess

intent (N) – purpose

fragments (N) – pieces that break away from something larger

metallic (Adj) – having the appearance of metal

meteor (N) – a small piece of a comet, asteroid, or exploding star that travels through the atmosphere of Earth

meteorite (N) – a mass of stone or metal that has reached the earth from outer space; a fallen meteoroid.

path (N) – the route, way, or track

phenomena (plural noun) – phenomenon, an amazing occurrence of nature

recover (V) – find and collect

souvenir (N) – something we buy or keep as a reminder of an event or special occasion

streak (V) –make a long narrow mark (See picture above.)

team (N) – a group that works together, a team of scientists

track (V) – watch, follow where something goes (with telescopes)

Purpose vs. Result

Select the response from the list that best completes the sentence.
Compare your response to the feedback by clicking each "check" or the "check 1-10" button.

Scientists are studying meteorites they can understand their biological origins.

Feedback 1

They look carefully at the composition of meteorites they can learn about comets, exploding stars and other phenomena.

Feedback 2

Astronomers track where fragments fall they can recover them.

Feedback 3

Astronomers photograph the paths of meteors in the sky they can estimate where the meteor pieces will land.

Feedback 4

In this way, astronomers have recovered several meteorites they now have a large collection of meteorites.

Feedback 5

Peter Jenkins, a NASA astronomer, saw a meteor streak across the sky he and his team spent a week looking for the fragments.

Feedback 6

The team found nothing they made an announcement and asked the public (people) to help search for meteorites their backyards.

Feedback 7

Soon a woman called reporting that she had found a large black, metallic rock that had bounced off her roof the team went and checked out "the rock".

Feedback 8

It was, indeed, a meteorite that had hit her roof. She took a picture of it as a souvenir and then gave the meteorite to the astronomers they could study it.

Feedback 9

10.

Later the team returned it to the woman she could show it to her insurance agent and get her roof repaired.

Feedback 10