might in past...

[eliff]

Hello,

I found this sentence in your archives.
'A It may rain today.
B (reporting the same day) He said it may rain today.
The next day
He said it might rain yesterday.' by Tdor teacher.

It is reported speech.It is correct.But;

.I thought that you might achieve that problem yesterday.

.I thought that you might do it.But you didn't.

Can we use might as a past form of may like that?
Thank you..

[Raymott]

Hello,

I found this sentence in your archives.
'A It may rain today.
B (reporting the same day) He said it may rain today.
The next day
He said it might rain yesterday.' by Tdor teacher.
---------------------
It is reported speech.It is correct.But;

.I thought that you might achieve that problem yesterday.

.I thought that you might do it.But you didn't.

Can we use might as a past form of may like that?
Like what? As in Tdol's example? Yes, that is one accepted use of "might'.
Thank you..

Your second example is obscure. You haven't used "may" in a reference sentence so it's impossible to say if your sentences are correct past forms of the missing sentences.

[J&K Tutoring]

"I thought that you might achieve that problem yesterday" is incorrect.

[Tdol]

You could say I thought you might have achieved it yesterday.

[eliff]

'I thought that you might achieve that problem yesterday.' is incorrect.

But;

''.I thought that you might do it.But you didn't.''

Is it correct if we use it like that? Because there is no adverb of time.

[Raymott]

'I thought that you might achieve that problem yesterday.' is incorrect.
By the way, you don't "achieve problems". You [re]solve problems or achieve results.
"I thought that you might resolve that problem yesterday.'' - This is a correct sentence, and it can mean a few things depending on context.

But;

''I thought that you might do it. But you didn't.''

Is it correct if we use it like that? Because there is no adverb of time.
Yes, that is correct.

You don't need an adverb of time if the context makes it clear.

[emsr2d2]

Sorry, but can someone tell me how one "achieves a problem"?

[eliff]

I took a look into a few grammar books and it is written like that:

1) I thought that you might resolve that problem yesterday.

2) You might resolve that problem yesterday.

It is written that they are incorrect and they are not the past of may.

I am so confused. :/

[eliff]

Could you tell me whether they are correct or not?

[5jj]

Could you tell me whether they are correct or not?

Raymott has said that they are correct. I agree that they are possible.

I thought that you might (re)solve that problem yesterday; I am pleased that you did.
I thought that you might (re)solve that problem yesterday; it's a pity that you didn't.