英语中的感官动词（verbs of perception）用来描述人的感官动作。常用的感官动词有：see（看见）、hear（听见）、notice（注意到）和 watch（观看）。
 
Hi, Saskia for BBC Learning English here. And today I'm going to tell you about how we use verbs of perception in English.
There are a number of these verbs, but I'm just going to look at two with you now: see and hear.
When we use these verbs, this is the form: first, the verb of perception; then, the object of the sentence; then, we have either the infinitive without to or the -ing form. Here's an example: 'I heard him go down the stairs' or 'I heard him going down the stairs'.
There's a slight difference between these two forms. When we use the infinitive, it suggests that we hear or see the whole action or event. Using the -ing form suggests that we hear or see something in progress.
'I saw her cross the street' means I saw her cross from one side to the other. 'I saw her crossing the street' means I saw her in the middle, on the way across.
 
用法总结
1 句式结构
① 感官动词 + 宾语 + 动词原形
I heard him go down the stairs.
② 感官动词 + 宾语 + 动词-ing
I heard him going down the stairs.
 
2 用法区别
① 感官动词 + 动词原形
感官动词后接动词原形，表示 “看到或听到整个过程或事件”，强调动作的完整性。
I heard him go down the stairs.
I saw her cross the street.
② 感官动词 + 动词-ing
感官动词后接动词-ing，表示 “看到或听到进行中的动作”，强调动作的连续性。
I heard him going down the stairs
I saw her crossing the street.