“by+时间”用法.pdf

。
“by+时间”意为“不迟于(=not later than)”；“一到(=as soon as)”；“当某时候到了
[=when (the time in dicated ) comes]”；“到…时为止”等。时间上有过去、。
“by+时间”意为“不迟于(=not later than)”；“一到(=as soon as)”；“当某时候到了
[=when (the time in dicated ) comes]”；“到…时为止”等。时间上有过去、现在和将
来之别。主动词本身有动作与状态之分，其时态可为一般式、完成式、进行式或完成进行式。
现分述如下：
1、“by＋时间”与动作性强的动词连用时，主句多用于完成式。by 后的时间可指现
在、过去或将来时间点。如：By the time he was fourteen year sold ，he had learned
maths all by 14 岁的时候，他就已经自学了数学。
I shall have finished it by the time you come back. 你回来以前我就把它做完了。
By the end of the match, they had kicked two goals and we had kicked
赛结束时，他们踢进了 2 分我们踢了 4 分。They must have finished their work by this
。
但是，上述情况中当时间为将来时，主句动作发生在从句动作之后时，主句动词可用一
般时态。如：If you're not better by then, I'll take you to see the
不好些，我就带你去看病。
Can you finish this by tomorrow? 在明天以前你能做完这件事吗？
间或有用进行式的。如：By the end of the first week the head of the department
-可编辑修改-。
was saying very nice things about me. 第一周末时系主任给我多多美言了几句。
2、“by+时间”与表状态的动词连用多用于一般式。by 后时间可为现在、过去或将来
时。如：By the end of the century the population numbered about four million. 到
世纪末人口已经达到四百万左右。You can borrow my camera, but I must have it back
by five o'，但是五