It took several seconds for his eyes to _________(适应）to thedark.
If the sun were to __________（消失），what would the earth be like?
These teaching materials can be __________（改编）for older children.
Mr Smith __________ __________ __________ attend the meeting because he is too busy. （不可能）
I am sorry __________ __________ __________ __________ __________. （对不起，让你久等了）
The houses __________ __________ __________ __________ are on fire. （靠近学校的房子）