I don’t know _______ .
There are ________books on my desk. _______books is fifty.
Don’t waste time any more. Wang Jun __________to be the monitor yesterday.
They are _____little children that you can't look after ____many by yourself at the same time.
______she is only three years old, she knows a lot of English words.
There’s ________ 800-metre-long road behind ________ hospital.