Choose the correct options

1. I wish we
   [have bought|bought|had bought] energy-efficient light bulbs last month. Thus, our electricity bills would be lower and we would save natural resources.
2. If only this plant
   [uses|used|had used] cutting-edge technology and modern filters, since without them production can cause severe harm to the environment.
3. I wish you
   [didn't|hadn't|don't] constantly use disposable tableware as it creates a lot of non-biodegradable rubbish and thus pollutes the environment.
4. I wish people
   [think|thought|had thought] more about animal protection in the past centuries and restricted hunting. Then there would be fewer endangered and extinct animal species now.
5. I wish the alternative energy capacity
   [is|were|had been] extended so that wind, water, solar power, etc. [supply|supplied|had supplied] all the current world's energy needs.
6. I wish humanity [has been using|was using|had been using] natural resources more rationally nowadays.
7. If only people [had found|could to find|have found] a solution to such global problems as air and water pollution in the previous century.