However only until can be used with less precise time expressions.

然而，只有 until 可以与不太精确的时间表达一起使用。

Late is a time expression, but it's not a precise time, it's a general time.

晚是一个时间表达，但它不是一个精确的时间，而是一个宽泛的时间。

Both by and until can be used with a precise time, an exact time.

By 和 until 都可以和精确的时间一起使用。

They concluded that the extinction happened 5,600 years ago, which is a very precise time for a prehistoric extinction.

他们说灭绝大概发生在5600年前，对于史前的物种灭绝而言，这个时间已经非常精确了。

" By, " this is a really precise end time, but not a very precise beginning time.

“截止” ，这是一个非常精确的结束时间，但不是一个非常精确的开始时间。

At (precise time points) The preposition " at" is used to pinpoint precise moments, particular times of the day, and specific hours.

at + 具体的时间点介词“At”用于指出精确的时刻、一天中的特定时间和特定的小时。

The minister had inquired of Hester, with no little interest, the precise time at which the vessel might be expected to depart.

牧师很感兴趣地向海丝特打听了船只预计启程的确切时间。

She said she was surprised at just how much work went into writing a recipe - measuring every ingredient, determining precise bake times and writing introductions.

她说，她对写一份食谱所花费的工作量感到惊讶：测量每一种配料、确定精确的烘焙时间，并撰写导言。

The technology is getting to the point now where that microwave frequency isn't precise enough for the applications that require precise time, so we are now working to develop optical frequency standards.

这项技术现在已经到了微波频率对于需要精确时间的应用来说不够精确的地步，所以我们现在正在努力开发光学频率标准。

The Soviets put the precise time of sinking at 4: 03 am eastern time, and Moscow says there was no further loss of life aside from the three crewmen killed when a fire broke out Friday.

03。苏联政府表示，周五爆发火灾时，除了3人死亡外，就没有其他的人员损失了。

It might, perhaps, be a little difficult to ascertain either what sort, or what degree of absence, would subject a man to be taxed as an absentee, or at what precise time the tax should either begin or end.

也许，要确定哪种类型或何种程度的缺席会使一个人作为缺席者被征税，或者税收应该在什么确切时间开始或结束，这可能有点困难。