Rhetoric is the art of using language effectively.

Grammar maps out the possible; rhetoric narrows the possible down to the desirable and effective.

Grammar is the law of language, considered as language; rhetoric is the art of language, considered as thought. Grammar tells what is correct; rhetoric tells what is effective and pleasing.

Rhetoric is also thought as the science of oratory, and the art of speaking with propriety, elegance, and force.

e.g.

1. Close the door, dear.

2. Would you be so kind to close the door?

3. It’s a bit cold here. Can you close the door?

4. Would you like to close the door for me?

5. I would be glad if you could close the door.

6. Would mind closing the door?

We can see from above sentences that sentence 6 can express the speaker’s anger; sentence 1 & sentence 2 can be used among family members or friends; sentence 4 & sentence 5 can be suitable for expressing to the people with higher position or with the same ranks; sentence 3 is between sentence 4 and sentence 5. So we can express our emotion through using sentences with different rhetoric.

Learning rhetoric well is the most important thing for us in English writing.