The bad effects of smoking on our health

At first , I want to tell you that I have written this paragraph for two years in one of my subjects in the final exam (I want to tell you that I wrote this paragraph 2 years ago for a final exam in a class). I got bad marks in this subject and until now I didn't know my mistakes so , I'll rewrite this paragraph for you to correct it .
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Smoking is a very dangerous thing in our life. No one can deny that smoking is a bad custom (habit). Most of smokers know this fact but a little (few) who can give up it (it up).For more details that will explain to us some of the bad effects (side effects) of smoking on (to) our health it would be said that smokers have been shown to suffer (would be) higher rates of tissue necrosis and haematoma formation. Their fractures will need a longer time to heal than non-smokers. Nowadays, patients presenting with an open tibia fracture should refrain from smoking immediately to promote bone healing and to lower the complication rate. Finally, we can say that smokers must give up smoking. This is the best for them and their family. This is also what Islamic religion requires from us : to live in peace and get away from any damage that will harm us.

The bad effects of smoking on our health

At first , I want to tell you that I have written this paragraph for two years in one of my subjects in the final exam . I got bad marks in these subject and until know I don't know my mistakes so , I'll rewrite this paragraph for you to correct it .
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Smoking is a very dangerous thing in our life habit ("thing" is too general. Try to be specific).  No one can deny that smoking is a bad custom (almost same meaning as last sentence). Most of smokers know this fact but a little who few can give up it many struggle to quit (I think you mean "few people can give up smoking", but that's not true. You would rather say "many people struggle to quit smoking").

For more details that will explain to us some of the Smoking has many bad effects of smoking on our health (Also try to think about alternative ways of saying "bad". You can start with a thesaurus). it would be said that It has been shown that smokers have been shown to suffer higher rates of tissue necrosis and haematoma formation. Their Tissue fractures will need a longer time to heal than non-smokers.

Nowadays, patients presenting with an open tibia fracture should refrain from smoking immediately to promote bone healing and to lower the complication rate (I googled this sentence. It was copied directly from someone's paper. You should never do that without quotation marks and citation of that paper).

Finally, we can say that smokers must give up smoking. This is the best for them and their family (Nothing wrong gramatically with these two sentences, but not suitabe for writing. Try to avoid "we". Maybe you can say: In conclusion, smokers should give up smoking for the benefit of themselves and their family). This is also what Islamic religion requires from us : to live in peace and get away from any damage that will harm us.