XII. Put the verbs in brackets into the correct form. 1. We _____________ (stay) at home if it rains. 2. She will call you if she _____________ (have) time. 3. If it _____________ (not rain) tomorrow, we will go for a picnic. 4. If everyone ____________ (recycle) paper, metal and glass, we ____________ (not produce) so much rubbish. 5. If you _____________ (not water) plants, they _____________ (die). 6. If the weather _____________ (be) bad, we _____________ (not go) to the park. 7. We ____________ (save) thousands of trees if we ____________ (not waste) so much paper. 8. What _____________ (happen) if we _____________ (keep) polluting the environment. 9. If we _____________ (not stop) cutting down so many trees, we _____________ (endanger) our oxygen supply. 10. If people _____________ (dump) chemicals into rivers, they _____________ (not be) able to swim in them in the future. XIII. Write the comparative or superlative of the adjectives in brackets. 1. It’s today ____________ than it was yesterday. (warm) 2. Rio de Janeiro is one of ____________ cities in the world. (beautiful) 3. The second question was ____________ than the first one. (difficult) 4. Australia is ____________ continent on Earth. (old) 5. China is ____________ country in the world. (populated) 6. My exam results were ____________ than I expected. (bad) 7. Ms. Nicholson is ____________ teacher I’ve ever known. (good) 8. The city is ____________ than it used to be. (crowded) 9. Tokyo is still the world’s ____________ city with 37 million inhabitants. (large) 10. Cool Blue Villa is one of ____________ houses ever built. (modern)