Lesson 5 Purpose
Lesson 5
Linking: Purpose
Links: to (so as to / in order to)
so as not to (in order not to)
so that (in order that)
in case
Adverbs: then, otherwise
STANDARD CONSTRUCTIONS
1. We’re getting up early tomorrow to catch / in order to catch / so as to catch the seven o’clock train.
- the full link for purpose if there is no change of grammatical subject (we) is so as to or in order to. However, this is usually shortened in informal English, so that purpose is then expressed only with the full infinitive (to catch…)
2. We’re leaving early so as not to / in order not to be late for work.
- the negative link if there is no change of subject is so as not to or in order not to; neither link can be shortened
3. I’ll lend you Sheila’s alarm clock so that / in order that you can be sure of waking up in time.
- if there is a change of subject (I -> you), the link is so that or in order that
- so that is normally distinguished from the similar link of result by its use without comma or tone change and by its use with can / could or will / would
- either so that or, more formally, in order that can begin a sentence:
So that you can be sure of waking up in time, I’ll lend you Sheila’s alarm clock. – this is another difference between so that used for purpose and so that used for result.
4. I left her a note last time in case she thought / so that she wouldn’t think someone had pinched her clock. (<- I left her a note last time. Otherwise she might have thought someone had pinched her clock.)
- when our purpose is to prevent what may or might happen, we very often use in case instead of so as not / so that… not
- in case (like if) is used used with present or past (including perfect) tenses, not with the future forms; and it is sometimes used with should:
I’ll leave / I left a note for Sheila in case she should think that …
5. Personally I always use two alarm clocks in case one of them doesn’t go off. (<- Personally I always use two alarm clocks, because one of them mightn’t go off.)
- when our purpose is to prepare for what may or might happen (because we cannot prevent it), we use only in case, not so as not / so that… not
6. I won’t take Sheila’s clock without asking in case I annoy her.
- when our expression of purpose begins negatively (won’t), we must use in case for prevention as well as preparation
Note:
Very formal alternatives to in case are lest and for fear that; you may come across them in literature, but will not use them actively in everyday English. They are normally used with should or the present subjunctive, e.g.:
A spare tyre is always provided lest a puncture (should) occur. = very formal
SHORTENED CONSTRUCTIONS
1. standard construction: Could you lend me that book so that I could show it to my dad?
-> shortened construction: Could you lend me that book to show (to) my dad?
- if in the standard construction the subject I and object it in the so that clause occur as objects in the main clause (me, that book), they are left out of the shortened construction
2. standard construction: I’ll give you this paper so that you can wrap the book up (in it).
-> shortened construction: I’ll give you this paper to wrap the book up in.
- if in the standard construction the object (the book) in the so that clause does not occur as an object in the main clause, it occurs in the shortened construction
- sometimes a preposition (in) is necessary to relate it to an object (the paper) in the main clause
Compare:
I’ll lend you my secretary to type your letters. X I’ll lend you my typewriter to type your letters with.
3. standard construction: I’ll leave the book here so that you can pick it up on your way home.
-> shortened construction: I’ll leave the book here (for you) to pick up on your way home.
- if in the standard construction the subject (you) in the so that clause does not occur as an object in the main clause, it is usually necessary to introduce it into the shortened construction by the use of for (i.e. for you in this case); however, it is not necessary in our example, since the context (on your way home) makes the meaning clear
4. standard construction: Mary McArthur sent her son shopping so that he would be out of the way.
-> shortened construction: Mary McArthur sent her son shopping to be out of the way.
X
5. standard construction: She sent him out so that she could get some peace.
-> shortened construction: She sent him out so as to / in order to get some peace.
- examples 4 and 5 show us that, since we may use only the full infinitive in the shortened construction when the subjects in the standard construction are different (Mary McArthur X he), we may have to add so as or in order to the full infinitive when the subjects are the same (She…she) in order to avoid being misunderstood. Without so as or in order the shortened construction in 5 might mean:
She sent him out so that he could get some peace.
!REMEMBER!
‘so that’ for result X ‘so that’ for purpose
The lecturer spoke with a strong accent, so that I didn’t understand all he said. = RESULT
I’ll leave the heating on so that the flat won’t get cold while we’re out. = PURPOSE
‘so that’ for result:
- is used with comma
- is not followed by modals can/could or will/ would
- cannot begin a sentence
‘so that’ for purpose:
- is used without comma
- is followed by can/could or will/would
- can begin a sentence: So that the flat won’t get cold, I’ll leave the heating on.
References:
Gethin, H. (1992) Grammar in Context. Harlow: Addison Wesley Longman Limited, pp. 60-65.