—Recent pressure at work may ______ his behavior.
--Who has broken the window in my room? --Who else _________ it but your naughty son!
. The concert by Lang Lang was so well _________ that all the tickets had been _________ on the first three days last month.
They _________ on the program for almost one week before I joined them, and now we are still working on it as no good results have come out so far.
--You look troubled. --Father asked me to finish this task today. How can I _________ ?
. After the earthquake, the Haitian(海地的)people needed to be helped _________.