The pronoun IT in “that helps to protect it from the sun's ultraviolet radiation” (paragraph 3), the pronoun THESE in “and these are often marked ozonefriendly” (paragraph 3), and the pronounTHEYin “and when they are cut down or burned” (paragraph 4), refer in the text, respectively, to:
Choose the alternative that presents the passive voice equivalent of the following sentence: Farmers are cutting down the trees to clear the land for farming.
Consider the sentences below: 1.Global warming ___________ by the greenhouse effect. 2.When ice in the poles melt, sea levels ____________. 3.Carbon dioxide __________ the sun's heat. 4.An American scientist ___________ holes in the ozone layer. Choose the alternative which presents the correct verb forms that complete the above sentences, respectively:
Choose the option which does NOT present a distinctive feature of the audiolingual method, but of the communicative approach to language teaching:
