If someone disagree with everything I have to say

Good morning, Ms. [Name]! ~

Thank you so much for doing your homework.

You did well in explaining your thoughts but I know that you can do a lot better. ^.~

Let\'s continue practicing later. See you!

~Teacher Elisha

 Then, I feel bad.

>> Then, I would feel bad.

or:

>> I will then, feel bad.

But I will try to explain him my opinions.

>> I will try to explain my opinions to him.

or:

>> I will try explaining my opinions to him.
 Nevertheless, If he continues to oppose, I will give up to explain.

>> Nevertheless, if he continues to oppose, I will give up explaining.

 And I\'ll avoid meeting him.

>> CORRECT!