Use the right form of the verbs in the brackets.
7. They (to have) a party at this time next week. 8. People (to pay) much attention to fashion nowadays? 9. When I (meet) him in the shop yesterday he (to buy) new equipment for his work shop. 10. When the student (to come) in, the teacher had already begun his lecture.

1 is, writes, has been writing, has already written 2 have you been doing 3 helps, has been helping, have already washed and dusted, are cooking 4 is running, has been running 5 what are they doing, are working, have been working 6 where is he now, is, is playing, have been playing 7 live, I have been lived, 8 works, has been working 9 have you found, I have been looking for it, but I haven't found it yet 10 have been playing 11 you have been sleeping 12 I have been waiting, but I haven't received it yet 13 she has already been doing, but she she hasn't done half of it yet 14 I have been waiting 15 what are you doing? I'm reading I have been reading, I have already read 60 pages 16 haven't heard 17 I have just received, but I haven't received any letters from my parents yet 18 is, the sun has been shining 

The poisoning of the world's land, air, and water is the fastest-spreading disease of civilisation. it probably produces fewer headlines than wars, earthquakes and floods, but it is potentially one of history's greatest dangers to human life on earth. if present trends continue for the next several decades, our planet will become uninhabitable.overpopulation, pollution and energy consumption have created such planet-wide problems as massive deforestation, ozone depletion, acid rains and the global warming that is believed to be coused by the greenhouse effect.the seas are in danger. they are filled with poison: industrial and nuclear waste, chemical fertilisers and pesticides. the mediterranean is already nearly dead; the north sea is following. the aral sea is on the brink of extinction. if nothing is done about it, one day nothing will be able to live in the seas.