英语可以说：see sb doing sth / see sb do sth
那样他们被动语态的时候后面如何跟非谓语动词呢，近期看到两个句子，想了解他们是如何来的：
1. Though women were watched to have the same chewing pace as men, they chewed each mouthful more times, slowing down the total time it took them to eat their meal.
这里为何用 to do，不是 doing？
2. In the video, the man can be seen holding his mobile phone in his hand after falling asleep on a Metro, with a message in large font on the screen which reads, “Please wake me if you need my seat.”
这里为何用 doing，不需要 to do 呢？
你第一要了解 see sb doing sth 与 see sb do sth 有什么区别：
1. see sb doing sth：看见某人正在做某事（doing 指动作正在进行）
I saw her crying. 我看见她正在哭。
2. see sb do sth：看见某人做了某事（do 指动作的全过程）
I saw her enter a bank. 我看见她进了一家银行。
下面大家来对比剖析一下：
1. 假如说：I saw her cry. 这多少就有点奇怪，由于这里用 cry，表示动作的全过程，即它表示“你把整个哭的过程都看完了”，也就是说从她开始哭到结束哭，你都在看着。这是否多少有点奇怪？
2. 假如说：I saw her entering a bank. 则比较正常，但它与I saw her enter a bank. 在含义上有不同：
I saw her entering a bank. 我看见她正走进一家银行。（指进入银行那一瞬间——背景：可能是碰巧看到的）
I saw her enter a bank. 我看见她进了一家银行。（指看见她来到银行门口然后走进银行的整个过程——背景：可能是在跟踪她）
弄清了以上不同就好办了：see 用于被动语态时，不同跟上面是一样的。
She was seen to enter a bank. 有人看见她进了一家银行。
She was seen entering a bank. 有人看见她正走进一家银行。
