Раскройте скобки, поставив глаголы в нужном грамматическом времени 1.yesterday nick(to come)from school very late. 2.he(to see)him by the end of the next year. 3.hello! where you(to go)now? 4.i(to help)my mothers tomorrow.

1. came
2. will have seen
3. are you going
4. will help

1 came, тк есть слово Yesterday, указывающее на время
2 не знаю
3 Where are you going now? , тк есть слово now, указывающее на то что действие происходит в данный момент
4I will help... , тк есть слово tommorow ( завтра)

Перевод:
But, the main problem is a pollution of our earth garbage. Than it is important? All our country will be in garbage soon, I think, it not what we dream of. We have containers for sorting of garbage, but very few people sort it. And, we have no overworking plant which this garbage would process. There is such settlement - Gribovichi at which a huge a lot of garbage, together which could be the nature, trees which would purify air. It is a pity, but there is no state spare cash.
It is necessary to construct somewhat quicker such plant, it will help to purify air, our country and the country will become a little better. We have to watch purity in our city. Otherwise we won't be able to live.
         Отличной учёбы...

By the way, the main problem is that our Earth is full of trash and garbage. What is important in it? I think its not our big dream that our country very soon will be sinking in the garbage. We have containers for trash sorting, but there are only a few of us, who is sorting this trash. Also, we dont have any refinery that would sort this sweepings. There is a inhabited locality called Gribovichy, which has an enormous heap of litter, instead of which there could be nature, trees, whos main work is to clean our air. Sadly, but the government doesnt any extra money. All we need is to quickly bild that refinery that will help to make our air and our country cleaner. We are obliged to look after the cleanliness in our city. And if we wont do this, we wont be able to live.