第一节：单选题（共25小题：每小题1分，满分25分）
从A、B、C、D四个选项中，选出可以填入空白处的最佳选项
1. ---What do you think of the grammar book?
--- Oh, it really is _____useful reference book, which is worth reading _________ second
time.
A. a; a B. an; the C. an; a D. the; the
2. He got ______ when he tried to save the child from the ______ house.
A. to burn; burning B. burn; burned C. burning; burned D. burned; burning
