比一比，填一填。

“有心栽花花不开，无心插柳柳成荫”，“插柳”采取的方法是（    ）

     Tom and Mike are good friends. They are good with children. They want to find jobs in summer vacation. This Friday Tom tells Mike that Sunson School Trip needs teachers to help with sports, music and computer. Mike is glad to know that.
    Tom can play basketball, volleyball, and he can swim. Mike can play the violin, the trumpet, the drums and the guitar, and he can swim,too. Tom and Mike like computers very much. Can they join Sunson School Trip?

十把钥匙开十把锁，你不知哪把钥匙开哪把锁，最多要试____次可把钥匙与锁配对。

判断对错.

10以内所有质数的和是15．