here's what i did for number 4.

The world is deserting because we are taking water for granted. If people continue to waste water, the earth’s structure will change and it will be the main cause of earthquake and potentially a tsunami.

and for number 5.

5. People prefer to live in the city than in country side. The number of people in the city grows every day. Clearly, there are more unpaved than paved land in the world. According to a hydrologist, he said that in 50 years from now there will be a collapse of the planets water structure because of the damage in the earth structure.

That's an incorrect use of the verb "is deserting." That verb means to abandon someone or something.

But surely, you don't mean the whole world is becoming a desert, do you?

And how would you prove the second sentence in #4? Someone is sure to question you about that one!

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5. People prefer to live in the city rather than in the country. The number of people in cities grows every day. Clearly, there are more unpaved than paved land in the world.<~~That seems not to fit what you're trying to prove here. According to a hydrologist, 50 years from now there will be a collapse of the planet's water structure because of the damage in the earth structure.<~~You really need to cite this -- and maybe quote the hydrologist.

Now ... I am not going to go through the rest and correct every single error. Your teacher will know that you didn't make the corrections, and you won't be able to write like this in class. So ... go through ALL your sentences and make sure there are no run-ons. Also, check every word and make sure it's used correctly.