基本语法
1. SuCh things can no__________(long) be allowed to go on.
2. The old woman used__________(be) kind to those animals.
3. __________(difficult) the questions are,__________(likely)I am to be able to answer them.
4. He would rather__________( listen) to others than __________(talk) himself.
5. Tom was willing __________(learn)to play chess with me.
