2. It is well known that China's great achievements in economic and social development over the past 30 years cannot be _____ its continuous efforts to push for rural reforms.
--- Tom , why didn’t you answer my call yesterday afternoon? --- Sorry , I didn't hear the phone . I ___________ asleep.
If you want to change for a red one you'll have to pay ___________ $ 20.
September 18, 1937 is a day _______ all Chinese will remember forever.
There are some health problems that , when _______ in time , can become bigger ones later on.
You will be surprised how quickly you _____ the money , so it is worthwhile to make a plan in advance.