Purchased used 2000 Honda Accord. Previous owner did not replace timing belt at 110,000 miles but said mechanic check it and it was okay. Can timing belt be checked? Should we quickly replace it?

According to the following site, Don't gamble on timing belt replacement Honda recommends that the timing belt be replaced at 105,000 miles. So, my suggestion would be to have the timing belt replaced rather than gamble with the potentially very expensive repercussions of not doing so. You might want to also check out the article on the link.