• 8. The subjunctive mood in adverbial clauses of purpose

I. The Subjunctive Mood is used in adverbial clauses of purpose introduced by the conjunctions: so that, in order that.

We use: the form may/might or can/could + Infinitive (i.e. the analytical subjunctive with the mood auxiliary may/might or can/could for all persons) if the predicate of the principal clause is in the present or future tense. When the predicate of the principal clause is in the past tense only might/could/should are used. Sometimes the Indicative Mood (the Future Indefinite) is used in Adverbial Clauses of Purpose instead of modal phrases.

The conjunction ‘so that’ is more common than ‘in order that’, and is used in less formal situations.

I tell you this Я говорю вам это,	so that in order that чтобы	you may/might understand the situation. you can/could understand the situation. you will understand the situation. (the Indicative Mood) вы поняли ситуацию.
I told you this Я сказал вам это,	so that in order that чтобы	you might understand the situation. you could understand the situation. you should understand the situation. you would understand the situation. (the Indicative Mood) вы поняли ситуацию.

• She opens (will open) the window so that she may/might/can/could/will get a breath of fresh air. Она открывает (откроет) окно, чтобы получить глоток свежего воздуха.

• She opened the window so that she might/could/should/would get a breath of fresh air.

• I gave her my address so that she might/could/should/would contact me.

• She left the lamp on the window-sill in order that he might/could/should/would see it from afar. Она оставила лампу на подоконнике, чтобы он увидел её издалека.

• She is learning English so that she may/might/can/could/will study in Canada.

• We arrived early so that we might/could/should/would get good seats.

Note the negative after so that and in order that.

• I came early so that I might not miss anything. (should not and would not would be possible, but not could not)

II. The Subjunctive Mood is used in adverbial clauses of purpose introduced by the conjunction: lest. (literary style) Lest has a negative meaning (чтобы не).

We use: the form should + Infinitive (i.e. the analytical subjunctive with the mood auxiliary should for all the persons)

or the Present Subjunctive (i.e. the same form as the Infinitive without the particle to)

or the Past Indefinite (if the predicate of the principal clause is in a past tense).

She opens the window She opened the window Она открывает/открыла окно,	lest чтобы не было душно.	it should be stuffy. it be stuffy. (the Present Subjunctive)
The girl whispered these words Девочка прошептала эти слова,	lest чтобы он не подслушал её.	he should overhear her. he overhear her. (the Present Subjunctive) he overheard her. (the Past Indefinite)

• He ran away lest he should be seen. Он убежал, чтобы его не увидели.

• Call me lest I forget. Позвони мне, чтобы я не забыл.

• He got up cautiously lest she woke up. Он встал осторожно, чтобы не разбудить её.

Note: To talk about the purpose of something we can use ‘in order/so as + infinitive’ when the agent of that infinitive is the same as the subject in the sentence.

• He took the course in order to get a better job.

• Trees are being planted by the roadside so as to reduce traffic noise.

In spoken English it is much more common simply to use a to-infinitive without ‘in order’ or ‘so as’ to express the same meaning.

• He took the course to get a better job.

• Jack went to England to study engineering. Джек поехал в Англию изучать инженерное искусство/технику.

To make a negative sentence with ‘in order/so as + infinitive’, we put ‘not’ before the to-infinitive. You can’t use a negative if you use only a to-infinitive.

• I carried the knife carefully in order/so as not to cut myself. (not: I carried the knife carefully not to cut myself.)