throw someone in at the deep end — to make someone do something difficult, especially a job, without preparing them for it or giving them any help [thefreedict]

My driving instructor is a nice and brave English old man. Though today was only the second session, he let me take the full control of the wheel on a busy road, and kept giving me instructions: “More gas please! Much faster!”. I dare not speed up as I could not help worrying we might hit someone. My body muscles tense, I tried to follow his instructions, fumbling for the clutch, brake, gas pedal, handbrake, and signal lights. Thanks, God. The instructor finally called for a break.

He handed me a sweet candy. ” You should smile while driving, ” he said to me with a grin, “My training method is to throw you in at the deep end. It’s like throwing you into the deep water so you can learn swimming quickly.” Suddenly, I had the thought: “Why should I be worried? He throws me into this crazy traffic. He should really be one who feels nervous on the seat.” I felt relaxed. Seeing me smile, the old man was excited: “Right! That is what I am talking about.”

know of someone/something — to have information about someone or something [thefreedict]

On “Frasier”, Niles is chatting with a friend about a legendary connoisseur of wine tasting. When asked whether he knows the person, Niles replies: “I don’t know him. I just know of him.”

take the edge off — Ease or assuage, make less severe [dict]

On “Frasier”, Frasier is upset with something. His brother, Niles, tries to comfort him: “Have a beer. It really takes the edge off.” Suppose you are sitting just next to a sharp cutting instrument. How will you feel if those pointy edges are blunted or removed?

red herring — something intended to divert attention from the real problem or matter at hand; a misleading clue [dict]

The origin of this phrase comes from this story: a hunted fox throws off a hound by dragging a red herring along a wrong trail. The hound follows the strong smell of the herring, and hence loses the quarry. One use of this phrase is seen below (from Economist):

“The bilateral trade imbalance, the target of so many American politicians’ anger, is an economic red herring.”

call of nature — A need to urinate or defecate [dict]

Sometimes, people may say someone has left to answer the call of nature — it is just an euphemistic way to say that he went to the toilet.

hold with — to approve of [dict]

On “Lord of the rings”, While eating Elvish biscuits, Sam says to Frodo: “I don’t usually hold with foreign food, but this Elvish stuff, it is good.”

butt out – to stop meddling in the affairs or intruding in the conversation of others [dict] , also see “butt in“.

On “Frasier”, Frasier desperately wants to make up the lost kinship with his son. He asks his son to play games together, but gets indifferent response. Frasier’s father says: “The boy has a life. You better butt out.”

Give someone the boot – To fire/dump someone by force [idioms]

On Frasier, Niles wants to spend some lone moment with Daphne, but there is a guest in their house. When Daphne is preparing some wine in the kitchen, she asks Niles about the guest, and Niles replies: “I have given him the boot.”