At no time does the salesgirl get up late in the morning, for she is always too busy _____ a good rest.
Nearly________ of the surface of our planet is covered by water.
It's said that __________ is going to give us a lecture.
----Would you please lend me the dictionary? ---- ____.
Who is it up ____ decide whether to go or not?
Wang Mei is one of many Chinese teenagers _____ “on the go”