2. I have modified my resume and attached it to this letter.

3. Again, I send my regards.

Are these sentences correct?

1. correct

2. “I have modified my resume and attached it.”

3. “Again, I send my regard.”

1. Thank-you in advance for your kind attention to this matter.

2. I have attached an updated resume.

3. Yours Sincerely,

2) I have attached (enclosed) a modified resume

3) I send my regards.

Your language, while technically mostly correct, is stiff and awkward. I would guess that English is not your first language.

1) “Thank you for your time and consideration.”

2) “I have modified and attached my resume.”

(if you are mailing it, say “enclosed” instead of “attached”)

3) “Again, I send my regards.”

Your language sounds very stiff and unnatural.

(saying you are very thankful is demeaning and makes you look like you are begging!!)

2. Enclosed you will find my modified resume.

3. Thanks again.

(don’t say that you send your regards; this does not sound business-like to me!!)

Americans leave out the u

color, not colour

neighbor, not neighbour

etc.

The British spellings are perfectly acceptable (but look funny to Americans)