Tìm lỗi sai trong các câu sau

tìm lỗi sai trong các câu sau
1 We left (A) the hall quietly (B) so that (C) not to disturb (D) the meeting
2 I don't know (A) what time (B) does she often come (C) home in (D) the everning
3 Gas is consumed (A) faster (B) than it (C) produces(D)
4The song (A) to that (B) we listened (C) last nigh was (D) beautyful
5 your dress looks (A) beautyful (B) . It must be (C) expensive (D)
6 when (A) I came into (B) the room , everyone were (C) talking happily(D) 
7 Hue , where (A) we visited during (B) our last summer vacation (C) , is a beautyful city (D)