the man

[navi tasan]

Which is correct:
1-I am thinking about the man yesterday.
2-I an thinking about the man from yesterday.
(A man that I saw yesterday.)

[Francois]

I don't know if it's appropriate for a non-teacher to post replies, but I would say "I'm thinking about the man I saw yesterday".
Maybe I'm wrong and a teacher will kill two birds with one stone

FRC

[navi tasan]

Thank you, Francois,

I don't think it is necessary to be a teacher to answer grammar questions on forums, but I do think it is better if one is a native speaker. In general, native speakers don't make grammatical mistakes. There are some non-native speakers who are as good, or maybe even better than the average native speaker, but I personally can't tell how good a non-native speaker is. So I prefer to ask native speakers, just to be sure.
If you are a native speaker, don't worry about not being a teacher. If you aren't a native speaker, then maybe we'll both learn something.

[Casiopea]

Which is correct:
1-I am thinking about the man yesterday.
2-I am thinking about the man from yesterday.
(A man that I saw yesterday.)

I agree with F. :D

Let's try some context: :D

Curtis: Who should we hire for the position?
Rod: I'm not sure. We've seen at least 12 people this week alone.
Sue: What about the applicant with marketing experience?
Rod: Do you mean the person we interviewed after lunch?
Sue: No. I'm thinking about the man from this morning. :D

All the best,

[navi tasan]

Thanks Casiopea,

So "the man from this morning" is correct. In this case you wouldn't say "the man this morning".

3-The man from this morning is suitable for the position.

Now, I have a second question.

Is this sentence correct:
4-The police officer this morning was a kind man.

I don't think we can say "from this morning" here, but I am not sure.