A．Pollution of the environment.B．A new generation of pest killers.C．Over－killing by hu

Which of the following cannot help solving the problem of pollution？A．Cutting out unnecess

A．Pollution of the environment.B．A new generation of pest killers.C．Over－killing by hu

Whats the central topic of the passage？A．Air pollution.B．Bonfires.C．Solid waste.D．Bonfires

The example of carbon pollution is used to illustrate______.A．transformation of language i

What is the main idea of the news item？A．The pollution across the world is more and more s

What is the topic of the news？A．Air pollution.B．Medicare in the U. S..C．The component of s