Определите время present tenses: present simple, present progressive, present perfect or present perfect progressive. 1.burning certain fuels (produce) sulphur dioxide.this (mix) with rainwater and ( cause) acid rain. 2.if the population growth (not, slow) down, pollution will increase. 3.the reality (be) that we all (use) up the world's resources-and simple lifestyle changes (can) (help) preserve the planet for future generations. 4."you (switch) off the light, dear? " she asked when we were leaving the house. 5. i (have) this bag for a year already. 6. how long you (use) your bike? 7. some countries (not, sign) the kyoto protocol yet and ( refuse) to cnhange the national way of life. 8. you (have) separate rubbish bins for paper, glass and aluminium in your locality? 9. look, it ( snow) heavily.it (snow) like that since morning. 10.at the moment many more people (drive) cars dangerously and carelessly.

1. Burning certain fuels produces (Present Simple) sulphur dioxide. This mixes (Present Simple) with rainwater and causes acid rain.
2) If the population growth doesn't slow down (Present Simple), pollution will increase.
3. The reality is (Present Simple) that we all use up (Present Simple) the world's resurecs and simple lifestyle changes can (Present Simple) help preserve the planet for future generations.
4. "Have you switched off (Present Simple) the light, dear?", she asked when we were leaving the house.
5. I have had (Present Perfect) this bag for a year already.
6. How long have you been using (Present Perfect Progressive) your bike?
7. Some countries haven't signed (Present Perfect) the Kyoto Protocol yet and refused (Present Perfect) to change the national way of life.
8. Do you have (Present Simple) separate rubbish bins for paper, glass and aluminium in your locality?
9. Look, it is snowing (Present Progressive) heavily. It has been snowing (Present Perfect Progressive) like that since morning.
10. At the moment many more people are driving (Present Progressive) cars dangerously and carelessly.