Cut the mustard

Context #1

John: Who are you going to choose for the front desk staff position?

Wick: I’m not sure yet. Both candidates are smart, but neither can cut the mustard.

John: You have to pick one of them though, right?

Wick: Not if they can’t meet our standards.

Context #2

Paulie: I’m not worried about next week’s competition at all.

Adrian: Why? You should never underestimate the abilities of an opponent.

Paulie: I know someone who’s been watching that team, and they say that their skills will never cut the mustard versus our team.

Adrian: Well if they can’t meet the expectations of the competition, they’re going to have a difficult time with our team.

Meaning: The expression "Cut the mustard" means to measure up to the standard or meet the expectation of something. (Usually this involves a set of skills, qualifications, and experiences).

http://languagesystems.edu/ 

To burn the midnight oil

Context #1: Ted and Wilma just finished an exam...

Ted: How was the exam?
Wilma: I think I did well, but I’m so tired, I don’t know for sure.
Ted: Really? What happened?
Wilma: I was getting ready for bed when I discovered that I didn’t read three chapters of the text book.
Ted: Oh no!
Wilma: Yes, chapters 16, 17, and 18! So I had to burn the midnight oil to catch up. I stayed up until 5am studying those chapters.
Ted: Uh, Wilma, I guess you were too tired to realize…those last chapters weren’t on the exam.

Context #2: Rhonda and William live in a dormitory.

Rhonda: I’m going to bed now. Goodnight, William.
William: Goodnight, Rhonda. Hey, where is your roommate?
Rhonda: Wendy? Oh, she’s at the library burning the midnight oil.
William: Wow! You mean she hasn’t finished her essay yet? That’s unfortunate.
Rhonda: Not for me! I’ll sleep well; I won’t have to hear her snore all night!

Meaning: To work all night. We use this idiom to emphasize the idea that a person is working hard after his or her normal work hours. In the old days (before electricity), people burned oil in lamps in order to light a room at night. If someone is “burning the midnight oil,” it means they need light in order to finish their work at night.

http://languagesystems.edu/ 

To hit the nail on the head

Idiom: To hit the nail on the head - get it right, get it, guess correctly, speak (the) truth

Context #1 – Students are in English class

Teacher: OK. Can anyone tell me what the word “affluent” means?

Student 1: To be sick?

Teacher: No, that’s not what it means. Good try, though. Anyone else?

Student 2: To have a lot of money or to be rich. For example, the new US president is very affluent.

Teacher: That’s right! You hit the nail on the head! That is exactly what it means and you gave a good example.

Context #2 – Two friends talking about a couple they know

Sara: Did you hear what Jim said about Winnie and Bill?

Pat: No, what did Jim say?

Sara: He said that Winnie and Bill are getting a divorce!

Pat: What? Jim hit the nail on the head! How could he possibly know that? I didn’t think anyone else knew about it.

Sara: Well, Jim overheard them fighting on Saturday and they must have mentioned it.

Meaning: To hit the nail on the head means get an answer to something correct or to speak the truth. In context 1, the second student answers the teacher's question about what the word means. In context 2, Jim speaks truthfully about his friends getting a divorce.  

http://languagesystems.edu/