In my native language, Persian, we do much use "Ke" which almost corresponds to "which, who, that" in relative clauses and many other cases (maybe in conversations to start or continue a narration or relate somethings ..., I myself don't know why or where)
Then, I would like to know how much it corresponds with "that" in English and if the sentences bellow with "that" are grammatical or sensible in a conversation or not?
Ummm.... (just literal translations)
1) The students who were absent, that I prefer not to mention their names, should do this practice...
2) We were walking, that suddenly a car stopped in front of us...
3) that you said I can't catch you, OK, now you see I did that... (conversation and not usual)
4) I was reading a book that he came
5) People who (that) can't accept it, that by accident are from your country, that off course are respectable, should know ....
6) I was so happy that I started to cry.
7) However, there could be other examples that I can't think of now.
If they are not grammatical, and if you yet understand them, what would be the correct sentence for each?