请根据括号中的中文提示、英文释义或句意,写出句中所缺单词,使句子通顺。
(1)We students should do many after-school____ (活动).
(2)People in different countries speak different l____ .
(3)It's ____ (hard or not easy) for me to play basketball well because I can't run fast.
(4)This boy doesn't know the____ (重要性) of study.
(5)L____ , he wasn't badly hurt yesterday.