1 C three - weeks -> three - week
2 D rings -> rang ( quá khứ tiếp diễn + when + quá khứ đơn )
3 A know -> knew ( If 2: If + S1 + V2/ed , S2 + would + Vinf )
4 B stay -> staying ( tobe used to + Ving: quen với )
5 B decorating -> decorate ( let's + Vinf )
6 D have you -> haven't you ( câu hỏi đuôi vế trước khẳng định nên vế sau phủ định )
7 A made -> was made ( câu bị động )
8 C dance with her friends -> dancing with her friends ( enjoy + Ving and + Ving )
9 C did he want -> he wanted ( câu khẳng định không phài câu ? )
10 B so -> because ( bởi vì )