A) Verb tenses
We change the tenses in the following way:
1. Present - past
"I never understand you," she told me. - She told me she never understood me.
"We are doing exercises," he explained. - He explained that they were doing exercises.
2. Present perfect - past perfect
"I have broken the window," he admitted. - He admitted that he had broken the window.
"I have been waiting since the morning," he complained. - He complained that he had been waiting since the morning.
3. Past - past perfect
"She went to Rome," I thought. - I thought that she had gone to Rome.
"He was thinking of buying a new car," she said. - She said he had been thinking of buying a new car.
4. Will - conditional
Will changes into the conditional.
"I will come on Sunday," he reminded me. - He reminded me that he would come on Sunday.
I shall, we shall usually become would.
"I shall appreciate it," he said. - He said he would appreciate it.
I should, we should usually changes into would.
"We should be really glad," she told us. - She told us they would be really glad.
May becomes might.
"I may write to him," she promised. - She promised that she might write to him.
The verb forms remain the same the following cases.
1. If the reporting verb is in the present tense.
Bill: "I am enjoying my holiday." - Bill says he is enjoying his holiday.
Sandy: "I will never go to work." - Sandy says she will never go to work.
2. When we report something that is still true.
Dan: "Asia is the largest continent." - Dan said Asia is the largest continent.
Emma: "People in Africa are starving." - Emma said people in Africa are starving.
3. When a sentence is made and reported at the same time and the fact is still true.
Michael: "I am thirsty." - Michael said he is thirsty.
4. With modal verbs would, might, could, should, ought to, used to.
George: "I would try it." - George said he would try it.
Mimi: "I might come." - Mimi said she might come.
Steve: "I could fail." - Steve said he could fail.
Linda: "He should/ought to stay in bed." - Linda said he should/ought to stay in bed.
Mel: "I used to have a car." - Mel said he used to have a car.
5. After wish, would rather, had better, it is time.
Margo: "I wish they were in Greece." - Margo said she wished they were in Greece.
Matt: "I would rather fly." - Matt said he would rather fly.
Betty: "They had better go." - Betty said they had better go.
Paul: "It is time I got up." - Paul said it was time he got up.
6. In if-clauses.
Martha: "If I tidied my room, my dad would be happy." - Martha said that if she tidied her room, her dad would be happy.
7. In time-clauses.
Joe: "When I was staying in Madrid I met my best friend." - He said that when he was staying in Madrid he met his best friend.
8. We do not change the past tense in spoken English if it is clear from the situation when the action happened.
"She did it on Sunday," I said. - I said she did it on Sunday.
We must change it, however, in the following sentence, otherwise it will not be clear whether we are talking about the present or past feelings.
"I hated her," he said. - He said he had hated her.
9. We do not usually change the modal verbs must and needn't. But must can become had to or wouldhave to and needn't can become didn't have to or wouldn't have to if we want to express an obligation.
Would/wouldn't have to are used to talk about future obligations.
"I must wash up." - He said he must wash up/he had to wash up.
"I needn't be at school today." - He said he needn't be/didn't have to be at school that day.
"We must do it in June." - He said they would have to do it in June.
If the modal verb must does not express obligation, we do not change it.
"We must relax for a while." (suggestion) - He said they must relax for a while.
"You must be tired after such a trip." (certainty) - He said we must be tired after such a trip.