Something has to be done to stop the rivers from being further polluted, ?
The English teacher laid particular ________ on the need of reading aloud.
________ the rainy weather,the streets were full of people on May Day.
Christmas is drawing near.Have you ________ a present for your best friend,Mary?
Washing hands frequently is one of the effective ways to avoid ________ by diseases.
The plane is ________ to arrive at 8 p.m.,but the foggy weather makes it hard to say.