Of the stars , the sun is _____ to the earth.

l never forget the days Ispent in Beijing University, hasa great effect on my life

Play computer games again? There’re two days left for the final exam! — _________you ________me? I’m too tired

Not until they left school how much their teachers loved them and helped them.

Recent campus tragedies show thatsafety measures are so important that we _______ take them too seriously.