I often doubt .
There are many tall trees on ______ side of the street.
Last weekend, an English short play was _____ in the second hall.
Few people knew how to use the Internet in the past,_____?
—What should we do before we use the blender?—I think we must read __________.
—How long ago _________ you _________ the English Club? —I _________ it since two years ago.