Interesting. Avoid this word as a perfunctory means of introduction. Instead of announcing that what you are about to tell is interesting, make it so. For example, delete “An interesting story is told of . . .” and tell the story without this preamble.

In connection with the anticipated visit of Mr. B. to America, it is interesting to recall that he . . .

vs.

Mr. B., who it is expected will soon visit America . . .

Kind of. Not to be used as a substitute for rather (before adjectives and verbs), or except in familiar style, for something like (before nouns). Restrict it to its literal sense: “Amber is a kind of fossil resin;” “I dislike that kind of notoriety.” The same holds true of sort of.

Less. Should not be misused for fewer.

He had less men than in the previous campaign.

vs

He had fewer men than in the previous campaign.

Less refers to quantity, fewer to number. “His troubles are less than mine” means “His troubles are not so great as mine.” “His troubles are fewer than mine” means “His troubles are not so numerous as mine.” It is, however, correct to say, “The signers of the petition were less than a hundred,” where the round number a hundred is something like a collective noun, and less is thought of as meaning a less quantity or amount.

(Taken from The Elements of Style by Strunk and White.)