Rain comes from clouds.(对划线部分提问）
Where-----does--rain come from?
另外还有：
I can see two desks in the picture.(对划线部分提问）
--What----- can -------- you see in the picture?
Can you piant fiowers?(作否定回答）
---No----,I can't----------.
He meets many other littie water drops.(改为一般疑问句）
-----Does--- he ---meet------ many other little water drops?
（N）we have some seeds.(改为否定句）
We --don't----- ---have---- ---any----- seeds.