用括号内所给词的适当形式填空，每空一词。
1. It is much ________(dry)in Yun Nan province than before because it hasn't rained for a long time.
2. My friend's ________(twelve)birthday is coming. Please help me choose a present for her.
3. Song Zuying sings very well. People like her sweet voice and she is a ________(success) singer.
4. Li Lei and Li Liang are twins, but there are many_________ (different) between them.
5. This is an easy problem. I think you can work it out _________ (easy).
1. _________2. _________3. _________4. _________5. _________