So that...

yougen · 2010-12-25, 10:31

Use so…that to place emphasis on a cause effect relationship between two clauses. So modifies an adjective or adverb in the cause-clause. (Note that very cannot be used in place of so.)
CAUSE
The meteor storm was so beautiful (adjective) EFFECT
that we watched it all night.
The meteor storm passed so quickly (adverb) that it went by in one night.

CAUSE
It was such a beautiful meteor storm(adjective + noun) EFFECT
that we watched it all night.
It was such a quick meteor storm (adjective + noun) that it passed by in one night.
Use such…that to place emphasis on a cause-effect relationship between two clauses. Such is used before an adjective + singular or plural noun, and such a is used before an adjective + singular count noun.

SO ……THAT SO … THAT
Use so that to introduce a clause indicating a purpose. So that is often used with can or could. (In order is also used for purpose.)
Use so … that to place emphasis on the cause. Use an adverb or adjective after so.
ACTION
We stayed out all night PURPOSE
so that we could watch a meteor storm. CAUSE
We stayed out so long (adv) EFFECT
that we were cold and tired in the morning.
We brought some blankets so that we could keep warm. The starts were so bright (adj) that we were amazed.

(a) I turned off the TV in order to enable my roommate to study in peace and quiet.
( b ) I turned off the TV so that my roommate could study in peace and quiet.
In order to expresses purpose.
In (a): I turned off the TV for a purpose. The purpose was to make it possible for my roommate to study in peace and quiet.
In (b) So that also expresses purpose. * It expresses the same meaning as in order to.

(c) I'm going to cash a check so that I can buy my textbooks.
(d) I cashed a check so that I could buy my textbooks.

So that is often used instead of in order to when the idea of ability is being expressed. Can is used in the adverb clause for a present/future meaning.
In (c): so that I can buy = in order to be able to buy.
Could is used after so that in past sentence.**

(e) I'll take my umbrella so that I won't get wet.
(f) I'll take my umbrella so that I don't get wet.
(g) Yesterday I took my umbrella so that I wouldn't get wet.
In (e): so that I won't get wet = in order to make sure that I won't get wet.
In (f): It is sometimes possible to use the simple present after so that in place of will; the simple present expresses a future meaning.
Would is used in past sentences; as in (g).
NOTE:
In order that has the same meaning as so that but is less commonly used.
Example: I turned off the TV in order that my roommate could study in peace and quiet.
Both so that and in order that introduce adverb clauses. It is unusual, but possible, to put these adverb clauses at the beginning of a sentence: So that my roommate could study in peace and quiet, I turned off the TV.
**Also possible but less common: the use of may or might in place of can or could: e.g., I cashed a check so that I might buy my textbooks.