句型转换。(18分)
（1）I can run fast.(变否定句)
I ________ run fast.
（2）I can jump high.(变一般疑问句)
________ ________ jump high?
（3）Can Sam jump very high？(作肯定回答)
________， ________ ________．
（4）I can jump far，can you？(作否定回答)
________， ________ ________．