Reported Speech

If we report what another person has said, we usually do not use the speaker’s exact words (direct speech), but reported (indirect) speech. Therefore, you need to learn how to transform direct speech into reported speech. The structure is a little different depending on whether you want to transform a statement, question or request.

We use a 'reporting verb' like 'say' or 'tell'. If this verb is in the present tense, it's easy. We just put 'she says' and then the sentence:

• Direct speech: “I like ice cream”.
• Reported speech: She says (that) she likes ice cream.

We don't need to change the tense, though probably we do need to change the 'person' from 'I' to 'she', for example. We also may need to change words like 'my' and 'your'.

(As I'm sure you know, often, we can choose if we want to use 'that' or not in English. I've put it in brackets () to show that it's optional. It's exactly the same if you use 'that' or if you don't use 'that'.)

But, if the reporting verb is in the past tense, then usually we change the tenses in the reported speech:

• Direct speech: “I like ice cream”.
• Reported speech: She said (that) she liked ice cream.

Tense	Direct Speech	Reported Speech
present simple	“I like ice cream”	She said (that) she liked ice cream.
present continuous	“I am living in London”	She said (that) she was living in London.
past simple	“I bought a car”	She said (that) she had bought a car OR She said (that) she bought a car.
past continuous	“I was walking along the street”	She said (that) she had been walking along the street.
present perfect	“I haven't seen Julie”	She said (that) she hadn't seen Julie.
past perfect*	“I had taken English lessons before”	She said (that) she had taken English lessons before.
will	“I'll see you later”	She said (that) she would see me later.
would*	“I would help, but..”	She said (that) she would help but...
can	“I can speak perfect English”	She said (that) she could speak perfect English.
could*	“I could swim when I was four”	She said (that) she could swim when she was four.
shall	“I shall come later”	She said (that) she would come later.
should*	“I should call my mother”	She said (that) she should call her mother
might*	"I might be late"	She said (that) she might be late
must	"I must study at the weekend"	She said (that) she must study at the weekend OR She said she had to study at the weekend

* doesn't change.

Occasionally, we don't need to change the present tense into the past if the information in direct speech is still true (but this is only for things which are general facts, and even then usually we like to change the tense):

• Direct speech: “The sky is blue”.
• Reported speech: She said (that) the sky is/was blue.

Sumber : http://www.perfect-english-grammar.com/reported-speech.html https://www.ego4u.com/en/cram-up/grammar/reported-speech