用括号中所给词的适当形式填空。
1. Our classmates are very________(friend) to me.
2. The ______(leaf) on the tree begin to fall.
3. — How often go to the library?
— ______(two)a week.
4. Please give my ________(greet) and best wishes to her.
5. — What's the weather like today?
— It's _______(sun).
