Yes.
Yes.
Yes.
Yes.
since yesterday afternoon is correct. since + the point-in-time ; for + time range.
no
It is incorrect. You may use "You saw him yesterday" as a statement or "You saw him yesterday?", as a question
"You saw him" would be correct in this context.
It could be: ''I had seen him twice yesterday, and he looked perfectly healthy; therefore, I was very surprised this morning to hear that he had died.''
The correct version is "I saw her yesterday."
"Thank you for delivering it to me yesterday"
No, you must say I was in London yesterday.
i did not went yesterday. is this sentnce correct?
I saw you yesterday. (past tense of to see)The verb seen is the past participle of to see, and uses a helping verb.(I might have seen you yesterday, I could have seen you yesterday)see - present, saw - past, seen - past participle.The past participle is used in present perfect sentences:I have seen the movie three times now.Or past perfect sentences:I had seen the movie before.And other tenses.
The former needs a subject, i.e. I did it yesterday. The latter requires a helping verb and a subject, i.e. I haddone it yesterday. With proper conjugation, they are both correct.
Since is used to specify or define a period of time. For example, "I have been writing this since yesterday night". "Since" in this sentence suggests that he has been doing it right from yesterday night. He has not done anything else. Or, "I haven't seen Marcy since Tuesday." In this sentence, the word "Since" suggests that the speaker has not seen Marcy from Tuesday. This means that the speaker has last seen her on Tuesday and not after that. Thus, it defines a period of time, i.e., for how long an action is being done or has been done and the like.