People can accept the fact that prices tend to rise year by year but at a(an) ______ rate.
The CDs are on sale!Buy one and you get ______ completely free.
It’s no use____ that you didn’t know the rules.
At a rough estimate(估计), Nigeria is ____ Great Britain.
In face of _______ failure, it is the most important to keep up ________ good state of mind.
Most of the factories under___________ have been designed by Chinese engineers.