Many city people        their bikes to work every day.

A. ride    B. will ride   C. rode     D. have ridden

Before you go to Canada, you need to learn more         it.

A. form   B. in     C. by    D. about

Everyone likes my father because       is friendly.

A. his     B. him   C. he    D. himself

根据短文内容及首字母提示完成所缺的单词

  Adults smile less than children do in a day．386 times less，in fact．As a result，we are becoming more and more unhappy and u________．

  All human beings are b________to know how to smile．Children are s________to smile up to 400 times a day．For them，a smile comes from their h_______and pleasure．Unluckily，as we grow o________，we smile less and less．

  “Adults only smile 14 times a day，”says Jamb，a researcher．That means we only smile e________two hours．

  “Life has so many problems that we have forgotten all the r________to smile，”she says．

  We just need to look for things that m________us smile．“Why are you afraid of a smile？”Jamb asks．Trying best to smile is the s______of your happy journey！And anyway，s________is a nice thing to do．

1．________ 2．________ 3．________ 4．________ 5．________

6．________ 7．________ 8．________ 9．________ 10．________

________（thousand）of students rushed out to celebrate their victory（胜利）．

They expected that they could solve the problem by________（they）．

________（polite），he drove the old man out of the room and shouted at him angrily．

Be careful to cross the street when we meet heavy________（traffic）．

My mother can’t sleep well，and sometimes she even stays________（wake）the whole night．

Is it possible for us human beings to leave all the animals in the________ ________（自然环境）？