Stork put soup in a tall jars so the fox can’t eat.
{A tall jar} should be in singular form. Also, use simple past tense.
Stork put soup in a tall jar so the fox couldn’t eat.

Be kind to your friends and they will be kind to you.
Good!

If you be bad they will be bad.
Pay attention to the form of {be} and your punctuation.
If you are bad, they will be bad.