___ I saw her, she was working in a shop

Air quality in our city is becoming worse and worse.—Yes. These days’ PM2.5 readings are frightening. Wemust do something to ______air pollution.

______ do you study in your English classes— I usually study by working with a group.

_these coins are of different shapes, sizes andcolors, they all date back to a long, long time ago.

His aunt’s lettershim of those beautiful days when they used to live together in his hometown.