The sequence of tenses means that the tense in the subordinate clause should agree with the tense in the principal (main) clause both logically and grammatically.

I n complex sentences with all types of subordinate clauses, except the object clause, the verb in the subordinate clause may be in any tense that reflects the actual time of the action.

She goes for a walk in the park when the weather is good.

She went for a walk in the park when the weather was good.

While I was watching TV, the telephone rang.

By the time he returned, I had typed ten pages of my report.

Note: the simple present is used instead of the simple future in adverbial clauses of time and condition referring to the future.

He will ask her about it when he sees her tomorrow.

She will visit them tomorrow if she has the time.

The sequence of tenses takes place in the object subordinate clauses and reported speech. Object subordinate clauses answer the question "what?" and stand in the place of an object after such verbs as "know, think, believe, understand, wonder, agree, say, tell, ask, answer, remark" and phrases like "I'm sure (that), I'm afraid (that)". Object clauses are connected to the main clause by the conjunction "that" (which is often omitted) and by other conjunctions, such as where, when, why, how, whether, if.

Rules of sequence of tenses

Main clause	Subordinate clause	Examples
a. Verb is in the present or in the future tense	Verb may be in any tense	I know that John has already left for Chicago. I know where she went.
b. Verb in the past tense (usually Past Simple):
1. The action of the verb in the main clause is simultaneous with the action of verb in the subordinate clause	Verb in Past Simple (Past Continuous)	I knew you were ready Я знал, что ты готов I told you that I was preparing for the lessons Я сказал тебе, что готовлюсь к урокам
2. The action of the verb in the subordinate clause is prior than the action of verb in the main clause used in Past Simple But: the concrete time is mentioned in the subordinate clause But: with the adverbs – the day before, two years before	Past Perfect Past Simple Past Perfect	I didn’t know that he had gone to the cinema Я не знал, что он ушел в кино I knew you were in the cinema yesterday Я знал, что ты вчера был в кино He said that he had gone the day before.
3. The action of the verb in the subordinate clause is later that the action of verb in the main clause	Future in the Past	I knew that he would go to the cinema Я знал, что он пойдет в кино
4. The subordinate clause includes the subordinate clause of time and condition	Past Indefinite	She said it would be a pity if I went into a factory Она сказала, что было бы жаль, если бы я пошел работать на фабрику
5. The subordinate clause expresses general truth	Present Simple	The teacher told us that the water boils at 100 degree.

3. Practice:

1. Translate the sentences into Russian:

1. He asked me if I had been in the new theatre. 2. He said that he was in the theatre at the moment. 3. She told me that she didn't like dresses. 4. She told me that her mother hadn't liked dresses. 5. We were told that she was ill.

6. She said that she was cleaning her room. 7. Lena thought that she would be back early. 8. They told me that they had been watching a film since four o'clock. 9. They told me that they were watching a film. 10. They were asked where they lived. 11. She didn't know why he had left.

2. Open the brackets and choose the right variant:

1. She realized that nobody (will come/would come).

2. We understood that she (sees/saw) nothing.

3. He said he (will arrive/would arrive) in some days.

4. My mother was sure I already (have come/had come).

5. I didn't know they (are/were) in the room.

6. We supposed the rain (will stop/would stop) in some hours.

7. He said he never (has been/had been) to London.

8. We wanted to know who (is singing/was singing) in the next room.

9. I always thought he (is/was) a brave man.

10. When I saw him, he (is working/was working).

11. We know she always (comes/came) in time.

12. She said she (has/had) a terrible headache.

13. We supposed they (will send/would send) us the documents.

14. He said he (has not seen/had not seen) us for ages.