词形转换。
1. write(名词)_________     2. left(反义词)________ 
3. dance(名词)________     4. piano(复数)________
5. knife(复数)_________    6. man(复数)_________
7. this(复数)__________    8. do(单三形式)_______
9. he(名词性物主代词)________   10. she(名词性物主代词)________