Ⅰ.用方框中所给单词的适当形式填空
1．Most of the waste paper can be ________．
2．Sue has different kinds of books.She often _________ them.
3．I ________ my bag to look for the key, but I didn't find it.
4．Danny cut his foot on a piece of________ glass.
5．It's ________ to swim in this deep river.
