What happened ________ Tom yesterday evening?

A．at               B．on               C．to               D．about

   Birthdays are strange things. The more you have, the more you try and pretend they don’t matter, and the more     1    . I’m not really sure why they think so. It’s true that you are getting older, but as     2     , “Who isn’t getting older every day?” The problem may be that a birthday reminds people of all the things    3    , but have not. I certainly understand that feeling, though I think     4     that I most want to do — a kind of personal re-ordering （重新排序） of the to-do list. What makes you depressed（郁闷） on your birthday is that you realize your re-ordered to-do list is exactly the same as it was last year. That makes you feel     5     , and not been anywhere. I have not had that experience this year. I look back at where I was last year and find things have changed since then.

Who is knocking ________ the door?

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