if后动词原形吗

Question

如题所述

Answer 1

都可以，但意思有别。接doing时强调动作正在进行，说瞬间的:接原形表示动作经常发生，强调整个过程。
如：i heard her singing just now。
i often hear her sing songs.
if后面是跟句子的，举例if做连词用于条件句中的用法。

a.If you study hard, you will pass the exam. 如果你努力学习，那么你就能通过这次考试。(真实条件)

b. If the boy should (或 were to) study hard, he would pass the exam. 假如这男孩果真努力学习，那么他就会通过这次考试。（句子含有“将来不大可能实现”的意味。）

If I were not busy now, I should (或 would) go to the meeting. 要是我现在不忙，我就去开会了。（对现在事实相反的假设，谓语都用虚拟语气。也可用情态动词 could, might 代替 should, would 只是含义不同。）

If he had not been busy yesterday, he would have come to the trade fairs. 假如他昨天不忙，他早就来贸易展销会了。（对过去事实相反的假设，谓语都用虚拟语气。注意和上句表示形式不同。）

I shall not go out if you come tomorrow. 如果你明天来，那我就不出去了。（这是真实条件。注意条件状语从句不用将来时态，要用现在时态来代替。在本情况下，主要靠主句谓语将来时态来判别。）

Answer 2

都可以，但意思有别。接doing时强调动作正在进行，说瞬间的:接原形表示动作经常发生，强调整个过程。
如：i heard her singing just now。
i often hear her sing songs.本回答被网友采纳

Answer 3

if后面是跟句子的，举例if做连词用于条件句中的用法。
a.If you study hard, you will pass the exam. 如果你努力学习，那么你就能通过这次考试。(真实条件)
b. If the boy should (或 were to) study hard, he would pass the exam. 假如这男孩果真努力学习，那么他就会通过这次考试。（句子含有“将来不大可能实现”的意味。）
I shall not go out if you come tomorrow. 如果你明天来，那我就不出去了。（这是真实条件。注意条件状语从句不用将来时态，要用现在时态来代替。在本情况下，主要靠主句谓语将来时态来判别。）
If I were not busy now, I should (或 would) go to the meeting. 要是我现在不忙，我就去开会了。（对现在事实相反的假设，谓语都用虚拟语气。也可用情态动词 could, might 代替 should, would 只是含义不同。）
If he had not been busy yesterday, he would have come to the trade fairs. 假如他昨天不忙，他早就来贸易展销会了。（对过去事实相反的假设，谓语都用虚拟语气。注意和上句表示形式不同。）

Answer 4

没有的。后面一般接句子