Tomorrow is Tom's birthday. Have you got any idea________the party is to be held?
— Why does the river smell terrible? — Because large quantities of polluted water _______ into it.
Xi’an was the last city ______ he visited when he came to China.
The music ______ she is dancing sounds beautiful.
______ time ______, what the scientist said finally proved to be true.
Mary never does any reading in the evening, __________.