It is not difficult to ______ Mr. Huang from among a crowd because he is above average height.
This ________ girl is Linda’s cousin.
Not until all the fish died in the river _____ how serious the pollution was.
The Smiths have gone to New York for their holiday, with an old servant ____ their house.
I was about to go to bed _____ one of my old classmates made a call to me.
Only those ____knew well could be let in.