Be careful not to ______ your bike with so many heavy bags.
--He didn’t go to the lecture this morning, did he?--__________Though he was not felling very well.
Excuse me. Do you know________.
--________ the population of Sichuan?--90 million people.
They are singing to ________ money for the poor children in rural areas.
How ________the woman is to save the boy from the danger of earthquake.