Myself

The word "myself" is a reflexive pronoun. Correct uses include the following:

• I shot myself in the foot.
  
• Nobody helped me make the bread, so I ate it all myself.
• I'm gonna sit right down and write myself a letter.

Sadly, I hear a lot of incorrect uses -- as a substitute for "me," or even "I."  For example, I have heard the following (slightly changed to protect the guilty):

• When you're done with that, give it to Bill or myself.
• Myself and John went to the concert.
  

Well known, educated people spoke the undisguised versions of the above.

Adverbial and adjectival phrases

In high school in the 1950s, I learned that "due to" begins an adjectival phrase, not an adverbial phrase. Thus, "The delay is due to circumstances beyond our control" is correct, but "Due to circumstances beyond our control, the game is delayed" is incorrect. 

I can see that few people observe this distinction anymore, but I nearly fell out of my chair the day I heard stock guru Jim Cramer mention it in passing.

A common misuse of an adverbial phrase occurs in sentences that start with "Firstly . . ." or "More importantly . . .." First, let me point out that "firstly" would be incorrect at the start of this sentence. More important, "more importantly" would be wrong at the start of this one.

Kinds of

People have little trouble with expressions like "what kind of dog is that?".  But make "kind" plural and confusion reigns.

Singular: kind of dog

Plural: kinds of dog or kinds of dogs?

From what I've heard, people seem to prefer the latter, even though the former is logically correct.

Further confusion arises when "that" or "those" enters.  If people mean "We get many questions of that kind," they often try to invert the order and say something jumbled like "We get many of those kind of questions."

If you like

I'm not sure what "if you like" means, but I often hear people say it after saying something that embarrasses them silghtly.

Associates

Recently I have heard companies refer to their employees as associates. I haven't done a study, but from the cases I remember, this usage seems more prevalent for lower paid workers. 

Beg the question

Nowadays, I often hear people say "that begs the question such and such."  They mean that the antecedent of "that" causes them to think of the question "such and such."

In logic, the expression "that begs the question" does not take a question in apposition with "question." Rather, it means that the antecedent of "that" is a an argument based on assuming what it claims to prove. For example, "God exists, because the Bible, which is the word of God, says so" begs the question.

Case of pronouns

Today, while watching a football game, I heard someone say that someone gave something "to he and I." Of course that should be "him and me." I think someone once told him not to use "him and me" as a subject, and the admonition made too deep an impression.

Then I heard Brooke Gladstone of NPR's On the Media say that someone should give a prize "to whomever can do . . .."  That should be "whoever," because, while the object of the  preposition "to" is a clause, a pronoun takes its case from its role in the clause. In this case, "whoever" is the subject of the the clause.

A little later, I heard someone use "we, the people" as the object of a preposition. I suppose they would argue that "we, the people" echoes the preamble to the US Constitution, which gives them license not to use the grammatically correct "us, the people." Maybe, but maybe not.

Phrases like "they say," "I believe," and so forth often trick people into using the objective case where they should use the nominative. The key to avoiding this error is to recognize that a phrase like "I believe" is parenthetical. For example, "George, whom I believe is a victim, just lost his job." The "whom" in that sentence should be "who." It is not the direct object of "believe."

"Whom" often turns up in place of "who" in the sentences of people who are unsure of the rules.