A thank you letter

Hey everybody! This is my first letter on this forum. If you would help me to correct any mistakes on writing such letters, I would be really greateful! The task text is below the actual letter.

Dear Sir or Madam,

I am an exchange student from Russia. I would like to thank you for your decision concerning my application for participating in exchange students programme.

I am studying at college of Toronto in the Information Technology department. I am coping with my studies so far. The family I live with are very friendly and helpful in supporting my staying in the foreign country. One of the best achievements is that now I am quite comfortable in understanding and keeping up during lectures conducted in fluent english.

I am glad to enjoy such an opportunity. I hope to participate in your other programmes in the near future again.

Yours Faithfully,
Mart Mets
(signature)

The task:
Imagine you are an exchange student in Canada. The Canadian Foundation is sponsoring your
studies. Write a thank you letter (80-120 words) to the chairperson of the organisation telling
him/her about
              √ the school you are studying at
              √ the family you are living with
              √ positive experience gained
Use the pen-name Mari Mets/Mart Mets for yourself. Do not write any addresses.

Nona The Brit wrote:

You should take another look at the highlighted areas. Dear Sir or Madam, I am an exchange student from Russia. I would like to thank you for your decision concerning my application for participating in exchange(for letting me participate in exhange) students programme. I am studying atthecollege of Toronto in the Information Technology department. I am coping with my studies so far. The family I live with are very friendly and helpful in supporting my staying in the foreign country. One of the best(?) achievements is that now I am quite comfortable in understanding and keeping up during lectures conducted in fluent(?) English. I am glad to enjoy such an opportunity. I hope to participate in your other programmes in the near future again(?). Yours faithfully, Mart Mets (signature

Thank you, nona the brit!
I've made some corrections (in bold). I have no idea what's wrong in the parts marked with (?) How about giving me a hint?

>conducted in English (of course the lectures are conducted in fluent language)

...is that now I am quite comfortable in understanding and keeping up during lectures that are conducted in fluent english

I meant it in general. As I am better now in understanding such lectures than before I went to Canada as an exchange student. In foreign countries, where english is not an official language, are some lectures in slower english. Does "that are" emphasize what I was trying to say?

Just another way of saying the same thing...................................................................Just look at it and see how you can improve yours

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

Dear Sir or Madam,

I am an exchange student from Russia. I would like to take this opportunity to thank you for allowing me the opportunity to participate in the Canadian Foundation Exchange Students Programme.

I am currently enrolled at the Toronto College studying Information Technology (IT).  I have adjusted to life here and am enjoying and doing well with my courses.  The family I am staying with is very friendly and has made my stay here very enjoyable.  As an added benefit, I have improved my understanding of both the oral and written English and can now comfortably understand lectures conducted in English.

I am grateful for this opportunity and hope to participate in any other programs offered by you in the near future.

Sincrely,

Mart Mets
(signature)