[Essay] Please help me proofread this letter and help polish it.

[rodgers white]

Dear ***,
How have you been ? You must be enjoying your life back home. We still miss the days we spent together.
Last term, we all benefited a lot from your lessons. We improved our oral English and become more confident to express ourselves. In addition, we learned so much about western culture and tradition.
On behalf of my class, I would like to thank you for teaching us English! We wish you joy and happinese in the new stage of life!
Yours,
***


The above is a kind of writing practice for my students. It presumes that the school English teacher has arrived back in the USA after his/her teaching work ended last term. The task is to write a Thank-you letter on behalf of your classmates to your English teacher, who devoted himself/herself to his /her teaching. The letter above is my own version. It serves as a possible version for my students. I hope someone would be so kind as to help me perfect it. Many thanks in advance.

 

[probus]

Became, not become. I am pretty sure that was just a typo.

More importantly, "to express ourselves" is okay but not the most perfectly natural usage. "In expressing ourselves" is better.

 

[teechar]

Dear ***,

How have you been? You must be enjoying your life back home. [STRIKE]We[/STRIKE] My classmates and I still miss the days we spent together with you.
Last term, we all benefited a lot from your lessons. We improved our oral English and became more confident [STRIKE]to[/STRIKE] in expressing ourselves. In addition, we learned so much about Western culture and traditions.
On behalf of my class, I would like to thank you for teaching us English! We wish you [STRIKE]joy[/STRIKE] success and happiness in your life. [STRIKE]in the new stage of life![/STRIKE]

Yours,

***

.