Drivers must stop when the traffic lights _____ red.
--Do you know when the Chinese custom_________ from?--It's hard to say. But its characteristics__________ the Tang Period.
--You went late the stadium yesterday evening, didn't you?--Yes, my wife was a little late _________ the supper.
After you have used the dictionary, please just put it back _____it belongs.
It is usually not quite cold in this area in March, but sometimes temperature ____be very low.
--__________ was it_________ they discovered the entrance to the underground place?--Totally by chance.