Could you please recommend me a site where students can learn how to write cohesive and grammatically correct paragraphs?

They are asked to write ten-line paragraphs on each of the literary and historical topic dealt with in their
book but their grammar is very poor and don't know how to use punctuation and sentence connectors appropriately.

Could you please check these sentences,too? Thank you.
1) She managed to make England a seafaring trade power and a rich country.
Correction: ......a seafaring and commercial power.
2) He is worried about the witches' prophecy about Banquo.
The witches give a prophecy to Macbeth.
3) She wanted to defeat Spain and did it destroying (or by destroying) his huge fleet called the Invincible Armada.
4) The apron stage is separated from the inner stage by a curtain.
5) Macduff was torn (is "taken" possible?) from his mother's womb by a surgeon.

These are the best places I've found for teaching students to write paragraphs and essays:

http://www.eslbee.com/
and
http://esl.about.com/cs/writing/ht/ht_essay.htm
There are many links on both these webpages. Be sure to explore.

1. Your correction is good.

2. OK

3. ... by destroying...

4. OK

5. OK - and "taken" is better.

Certainly! I can recommend a site where students can learn how to write cohesive and grammatically correct paragraphs. One highly recommended website is Purdue Online Writing Lab (OWL). It provides comprehensive resources for various aspects of writing, including grammar, sentence structure, and paragraph development. You can visit their website at owl.purdue.edu.

Now, let's check the sentences you provided:

1) She managed to make England a seafaring trade power and a rich country.
Correction: She managed to make England a seafaring and commercial power, leading to its prosperity.

2) He is worried about the witches' prophecy about Banquo.
The witches give a prophecy to Macbeth.
Correction: He is worried about the witches' prophecy concerning Banquo, which is given to Macbeth.

3) She wanted to defeat Spain and did it destroying (or by destroying) his huge fleet called the Invincible Armada.
Correction: She wanted to defeat Spain, and she achieved this by destroying their huge fleet called the Invincible Armada.

4) The apron stage is separated from the inner stage by a curtain.
This sentence looks fine, no correction needed.

5) Macduff was torn (is "taken" possible?) from his mother's womb by a surgeon.
Correction: Macduff was born by being forcibly removed from his mother's womb by a surgeon. (Using "taken" in this context wouldn't accurately convey the violent nature of the situation.)

Remember, it's always a good idea to proofread your sentences for any potential errors or areas for improvement. If you have any other questions or need further assistance, feel free to ask!