Our duty is to ______ their country against both domestic and foreign enemies’ attack.
| A．delay | B． defend | C．defeat | D．depend |
It is by no means clearthe president can do to end the strike.
| A．how | B．which | C．that | D．what |
When deeply absorbed in work, ________ he often was, he would forget all about eating or sleeping.
| A．that | B．which | C．where | D．when |
When you are done with the book, just give it to Lucy or Helen or __________.
| A．whoever | B．wherever | C．whatever | D．however |
Nothing is so easy as ________ parents to raise their expectations of their children too high.
| A．of | B．to | C．by | D．for |
Not until he retired from teaching three years ago having a holiday abroad.
| A．he had considered | B．had he considered |
| C．he considered | D．did he consider |