题目

There was no _____ in my old school. ( )A.library B.libraries C.a library 答案：【答案】A【解析】句意：我以前的学校没有图书馆。句子是there be句型的否定句，no = not a，was是单数，该空应当填library，故选A。铁丝在氧气中燃烧的现象是______，文字表达式为______，集气瓶中事先放少量细沙或水的作用是______．