By the time my mom _____ to our school, all others of my class ______ for home.
. —______ to the Shanghai? —No, never, but I went to Beijing a few years ago.
—How many students are there in the classroom? ____. They are all in playground.
I ______ my English teacher for two years.
I haven’t finished my work ________.
—David, can you tell me how to use this new camera? — . Let me have a look.