1. The United Nations has (ООН в единственном числе) meetings where world leaders agree on what to do about global warming. If there is too much pollution in the air, some people have (conditional - как факт.Если будет 1-ое условие, то точно произойдет 2-ое) health problems.
2. Ecologists looked for special spots on white pine trees to know if there
were(согласование времен, множественное число) high levels of ozone.
3.Many types of air pollution are invisible, but some can be seen(пассивный залог) with the naked eye.
4. The teacher asked the boys if they had done(согласование времен в косвенной речи) the task.
5.Satellite images proved that deforestation had increased (согласование времен) rapidly.
6.The passage is so difficult that I can't (по смыслу) understand it.
7.Experts said that less than 3 per cent of the water on Earth was(согласование) fresh water.
8.His health has improved since he returned (грамматические правила) from the hills.
9.If we had sorted the waste, we would have saved (3 conditional) millions of kilowatts of energy.
1.most often, my friends and I use our mobile phones. These gadgets are very convenient and can accommodate all useful applications and functions. On the computer that is on my work desk, I can play computer games or study. Also useful in my home TV on which I can watch the latest news, entertainment TV shows or movies.
2.The main drawbacks of some phones are a small screen or an old operating system that does not support modern applications. Fortunately, this problem was solved over time. Also, the main problem of phones is not only very addictive applications that literally drag into themselves. The problem of stationary computers is not their mobility, but with the advent of laptops, this problem has been solved. If you choose between a computer and a laptop, you need to choose between their capabilities and it is inappropriate to compare them.
3.It is possible to hang from a mobile phone and this problem exists today. Most of the world's population suffers from it. Often those who do not suffer from this problem have an old phone or laptop. You can only depend on interesting programs that you like because you always want to move away from programs for robots as soon as possible.
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