固定表达，在语境中理解。

在海上；茫然不知所措

The crew spent two nights at sea before reaching the island.

在某个时候；迟早；在某个时候；总有一天

At some point, the city will need to replace the water pipes beneath the old district.

处于风险中；关系重大；处于风险中；得失攸关

With the final grant at stake, the team checked every figure before sending the proposal.

当时；在那个时候；在那时；当时

At that time, I was working evenings, so I could meet the delivery driver in the morning.

在机场

We checked in at the airport two hours before departure.

在……后部；在……的后面

The emergency plan is posted at the back of the staff handbook.

在……开始时

At the beginning of each shift, the baker checks the oven temperature and records it in a notebook.

在……底部；在……末尾；在……底部；在……最深处

The spare batteries are at the bottom of the blue drawer beside the stove.

在……结束时；在……结尾

At the conclusion of the workshop, each participant received a printed guide.

在……的核心；是……的关键

Trust is at the core of a strong relationship between a teacher and a student.

以……为代价

The new wall blocks street noise at the cost of natural light in the reading room.

在门口；在门边

Someone was waiting at the door when I got back from the pharmacy.

立刻；毫不迟疑地

Mina is ready to help at the drop of a hat.

在最后；到……结束时

At the end of the shift, the supervisor checked the inventory and locked the supply room.

在……结束时；在……末尾；在……结束时；在……尽头

At the end of the lesson, the students wrote down one question they still wanted to ask.

归根结底；最终

At the end of the day, we all want the same thing: a safe place for our children.

以牺牲……为代价

As love genes spread at the expense of indifference genes, Loveless Bobs slowly become extinct.

处于……的前沿；走在……前列

The university's materials lab is at the forefront of research into safer battery storage.

遭受……的对待或伤害

The village suffered extensive damage at the hands of the invading army.

处于……的核心；是……的核心

Trust is at the heart of a strong working relationship, especially when plans change.

在医院（通常指到医院办事或探访）

Her brother stayed at the hospital until the test results came back.

在最后一刻；临到最后；在最后一刻；临近截止时

He changed the venue at the last minute, so several guests had to check the new address.

最迟；不晚于

The committee asked agencies to file their comments by 15 May at the latest.

此刻；目前

I'd like to comment on that, but I'm watching CNN at the moment and can't concentrate.

在办公室；在办公地点

We left the signed copies at the office so the manager could review them.

一开始；在初始阶段

All the problems the Republican radicals are belatedly recognizing now were totally obvious at the outset.

应……的要求；根据……的请求

At the request of local residents, the library now opens an hour earlier on Saturdays.

同时；在同一时间；同时；在同一时刻；同时；与此同时

The tablet records the meeting and takes notes at the same time.

与……同时；就在……的时候

At the same time as the new bridge opened, the city added a protected bike lane beside it.

当时；在那时；当时；那时；当时；那时候

At the time, we did not realize the bridge would close for repairs the next morning.

在……之时；当……发生时；在……发生时；在……之时

At the time of the fire, the kitchen staff were serving lunch in the main hall.

在……顶部；在……最前面

A small brass bell sits at the top of the staircase to welcome visitors.

至少；起码

At the very least, insurers should be allowed to distinguish these kinds of claims from others.

此时此刻；到了这个阶段；此时；在这一阶段；此时；到目前为止

At this point, we have checked every room, so the missing parcel must be outside.

在现阶段；目前

At this stage, the team needs one more week to test the new irrigation system.

目前；在这个时候

We don't have a final estimate at this time, but the contractor will send one tomorrow.

有时；间或

The route is at times slow, but it avoids the busiest part of downtown.

在工作；正在起作用

Maya is at work until six, so she will call us afterward.

单身派对；婚前派对

They organized a quiet bachelor party at a bowling alley before the wedding.

来回；反复；来回；反复往返；来回；往返

The two teams exchanged emails back and forth until they agreed on a date for the joint event.

后门

The delivery driver left the package by the back door as requested.

回到这里；在这里后方

The courier will be back here before noon with the signed papers.

回家；在家乡

We brought the borrowed blankets back home after the camping trip.

在过去；当年

Back in the day, my parents drove across the country with a paper map and no phone charger.

退后；收敛；不再施压

He backed off when she asked for more time, and they talked again the following week.

那时候；当时；那时候；当年

Back then, the village had only one small grocery store.

回到原点；重新开始

After the supplier canceled the order, the team was back to square one.

重新聚在一起；重归于好

After a year apart, the band is back together for a benefit concert.

倒霉；运气不好

It was bad luck that the ferry stopped running just as we reached the dock.

银行账户

She opened a separate bank account to save for her studio.