In order to write good essay in toefl exam - 1st you have think about topic for example if it ask for your opinion than decide and than look for reasons.

essay topic - it is better for children to study in countryside than in city? 

ur opinion - whether u agree or disagree? - No 

reasons: 1) exposure in city is better 

             2) Education - good schools and colleges

             3) can pursue hobby or learn extra curricular activities 

             4) employment rate is higher in cities - better future for kids

             5) prevent future migration to city and also better to learn tough n competitive life at an early stage. 

now based on these reasoning start writing - justify each point with an example which can be from ur own experience. 

Hope this will help u. 

Best of luck :)

I cannot run my time while trying to write an essay down,

the introduction is the most difficult part for me because I don't know how to express myself and which way is the best to capt someone's attention.

I'm always thinking about the rules I've read on this site which makes my task even tougher to achieve. But after '' trying'' to write the introduction there comes the next problem: the body and its 7 sentences that i must write but i don't know how, i really don't!

I mean, when i read others essays in this site it looks so easy and i clearly understand their ideas, but when it comes to me, it's just impossible. I mess everything up, and i don't know how to improve…

What does it take to write an essay??? How am I suppose to write only 15 words in a sentence if in total i have to have more than 300 words? What about fluency and ideas, I'd like to know how can I develop one subject whitout making a mess out of it by trying to explain it. Those are my main problems….

I hope to get a response, if possible… Thank you!!