Researchers discovered that plants______with a virus give off a gas that activates disease

听力原文： American researchers have made a discovery that might help them better understan

What did the researchers discover in northern Kenya？A．A human tooth.B．A human skull.C．Thre

Researchers cannot （) the possibility that Earth may one day run out of its orbit.

According to paragraph 2, what makes some researchers think that certain cave paintings we

Researchers at the University of Colorado are investigating a series of indicators that co

According to the news item, researchers would be most likely to agree that aircraft noise