Mr. Smith has two sons, one of____working as a bus driver.
We don’t need to do extra work this evening. The day’s work was almost ______ now.
--The button in the kitchen is out of order.--_______.
The heart is believed to _____blood into veins(血管) which are netted all over the body, thus keeping a person alive.
______addition to being creative, perseverance and diligence are necessary qualities to be a good scientist.
The gold loop discovered in the ancient tomb _____ to be _____ in studying the history of the Jin Dynasty.