Is it a correct sentence to say "I spoke to him by telephone."

Is it correct to say “I spoke to him by telephone.”

Yes, it is. You need a question mark after the closing quote marks.

by telephone = over the telephone = on the telephone

Correct?

Yes, Tofu.

Thank you, Mordant.

what is the difference in the usages of “may” and “might”

Nsreddy,

There are a lot of webpages you might be interested in.

englishbaby.com/lessons/3091 … /may_might
englishgrammarsecrets.com/maymight/menu.php
englishpage.com/modals/may.html
englishpage.com/modals/might.html
blogs.english4today.com/?p=26