核心词汇
1．A small child has to learn to keep its b_____ before it can walk far.
2．The South Pole isn’t i_________ by anyone up to now.
3．Christmas is an a______ festival for most of the people in the world.
4．The _______ (最低的)temperature in winter in my hometown is up to －20℃.
5．Medical assistance is available in case of an ____________(紧急情况)．
6．It was a ____________(荣幸) to make his acquaintance.
