Correct the mistakes in these sentences 1)who did help you to do your hometask 2)as we were watching him the small boy

1) Who helped you to do your hometask? 2) As we were watching him, the small boy suddenly ran away. 3) He sent a letter and I stopped worrying as everything seemed OK. 3) When we entered the club, a beautiful girl was singing. 4) It was very late, but when I entered his room he was reading a book. 5) When I was walking in the street last night, someone hit me.