Body-part idioms in English: meaning, context, and register

Do not translate a body-part idiom word by word. First, ask whether the literal meaning fits the situation. If a friend asks you to keep an eye on a suitcase, they need someone to watch it. The surrounding words tell you that the phrase is about care, not about a real eye.

Could you keep an eye on my bag while I buy a ticket?

Could you watch my bag while I buy a ticket has the same plain meaning.

A friend leaves a bicycle outside a cafe. Which plain phrase is closest to keep an eye on it?

Watch it carefully. The friend wants someone to make sure the bicycle stays safe.

Use keep an eye on when you want someone to watch a person, thing, or situation carefully. It often appears in short, friendly requests. The phrase can also describe ongoing care: A nurse keeps an eye on a patient after treatment. In a formal instruction, monitor may be clearer.

I will keep an eye on the oven while the children play outside.

I will check the oven timer at 6:00 gives one specific action rather than ongoing watching.

Do not use keep an eye on when you mean look at something only once. The idiom suggests continued attention.

Get cold feet means become nervous about a planned action and perhaps decide not to do it. Use it for situations such as an interview, a performance, a trip, or an agreement. It is informal, so it can sound playful or too casual when someone is dealing with a serious decision.

Lara got cold feet before she signed up for the climbing course.

Lara decided not to join the course because she was worried gives the meaning directly.

Does get cold feet describe calm confidence or nervous hesitation?

It describes nervous hesitation before a planned action.

Cost an arm and a leg means cost a lot of money. It is a strong informal exaggeration. Say it when you want to react to a price in conversation. For a budget, invoice, or complaint, state the actual amount and explain what the amount covers.

That small apartment costs an arm and a leg near the station.

The apartment costs 1,200 pounds a month gives a price that a renter can compare with other options.

Do not use this idiom to report a price where the number matters. The phrase tells the listener only that the speaker thinks the price is very high.

Lend a hand means help someone. It works well in a casual request when the task is already known or obvious. Add the task when it is not clear: Could you lend a hand with the boxes? In a formal request, name the help you need and any deadline.

Could you lend a hand with these boxes after lunch?

Could you carry the two boxes by the door asks for one specific part of the work.

Which reply fits this request: I can help for ten minutes, or I can lend you my gloves?

I can help for ten minutes fits. Lend a hand means offer help, not give someone a hand or an object.

Use see eye to eye when two people agree about an opinion, plan, or decision. Use on the tip of your tongue when you almost remember a word or name but cannot say it yet. Both expressions are common in conversation. A plain sentence can help when the listener may not know the idiom.

The two coordinators do not see eye to eye about the schedule.

Her name is on the tip of my tongue, but I cannot remember it yet.

The coordinators disagree about the schedule and I almost remember her name give the meanings directly.

Which idiom fits when you nearly remember a restaurant name but cannot say it?

Use on the tip of my tongue. It means that the name feels close to memory but is not available yet.