1 they are delighted that the water here is a polluted b unpolluted c pollute 2 most of the consumers want products working a effective b effect c effectively 3 what can we do to spend less lighting? a on b for c in 4 she often looks her brother when her parents are way a for b after c like 5 if nam his homework he will go with us a finishes b will finish c finish 6 she was because she couldn't pass her exam a happy b unhappy c unhappily 7 they had to stay at home it rained heavily a so b but c since 8 everyone must take part in deforestation a preventing b reducing c protecting 9 i'm that my school team didn't win the first prize a sure b delighted c disappointed 10 electricity gas water are very for our life a necessary b necessity c unnecessary 11 solar energy can be clean and it doesn't cause a polluted b pollution c polluting 12 we are looking forward from the local authorities a to hear b hear c to hearing 13 she suggest that you them to the party a should invited b must invite c will invite 14 we went working in the field although it was too dark a to b on c into 15 he wanted to watch the weather forecast so he turned the tv a on b down c off 16 she didn't go with us because she had to look my sister a for b after c up 17 i suggest the garden early in the morning a watering b to water c should water 18 there are ten years in a aren't there? a century b decade c millennium