8 Put the verbs in brackets into the appropriate tenses to form Type 1 conditional sentences.
1 If you use (use) less paper, you .......... (save) the rainforests.
2 The polar bear ...... (not/become) extinct if we...... (stop) global warming.
3 You ...... (waste) electricity if you ...... (leave) your computer on standby.
4 ........ the ice caps......... (melt) if temperatures ........(rise)?
5 If you ..... (ride) your bike, you ........(not/cause) air pollution.
6 We ........(reduce) waste if we......... (recycle) rubbish.

9 Rewrite the sentences. Use if or unless.
1 Unless we stop burning fossil fuels, global temperatures will rise. If we don't stop burning fossil fuels, global temperatures will rise.
2 If we don't help save the animals, they will become extinct.
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3 Unless we recycle more, we won't have a place for all the rubbish.
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