My favorite day of the week is Wednesday.
Because on Wednesday class is short, So I can play soccer and baseball with my friends, so I'm happy.



My least favlrite day of the week is Tuesday.
Because on Tuesday class is very long, So I can't play soccer and baseball.

Teacher, I'm sorry because I sent my homework late.

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1.
David: My favorite day of week is Wednesday.
Correct: My favorite day of the week is Wednesday.
Explanation:
*Use an article before a noun.

2.
David: Because on Wednesday class is short.
So I can play soccer and baseball with my friends.
So I'm happy
Correct: Because on Wednesday class is short, So I can play soccer and baseball with my friends, so I'm happy.
Explanation:
*Put a comma between related sentences.
*End your sentence with a period.

3.
David: My least favlrite day of the week is Tuesday.
Correct: My least favlrite day of the week is Tuesday.
Explanation:
*Be conscious of your spelling. ^^

4.
David: Because on Tuesday class is very long.
So I can't play soccer and basball.
Correct: Because on Tuesday class is very long, So I can't play soccer and baseball.
Explanation:
*Put a comma between related sentences.

5.
David: Teacher I'm sorry because I send homework late.
Correct: Teacher, I'm sorry because I sent my homework late.
Explanation:
*Put a comma after the name of the person you're talking with.
*It would be better if you say my to indicate ownership.

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Hello, David! Thank you for submitting your homework. Please read the following corrections and explanations carefully. If you have questions and clarifications, you can ask me in our class. Thank you!