33. I cannot understand__________the boy alone.
We are all____ of the poem “Children, quickly, hold mother’s hands” and moved by it.
Scientists say it may be five or six years_______it is possible to test this medicine on human patients.
You have to ____smoking. It isn’t good for your health.
---Must he remember everything he has learned in the class? ---No, he _____.
---“Don’t read in bed.” --- What did he said? ---He told us _____read in bed.