感官动词 + doing/( to) do
感官动词 see, watch, observe, notice, look at, hear, listen to, smell, taste, feel + do 表示动作的完整性，真实性；+doing 表示动作的连续性，进行性
I saw him work in the garden yesterday.
昨天我看见他在花园里干活了。
(强调”我看见了”这个事实)
I saw him working in the garden yesterday.（强调”我见他正干活”这个动作）
昨天我见他正在花园里干活。
典型例题
1）They knew her very well. They had seen her ___ up from childhood.
A. grow B. grew C. was growing D. to grow
答案：A。
因题意为，他们看着她长大，因此强调的是成长的过程，而非正在长的动作，因此用see sb do sth 的句型。
2）The missing boy was last seen ___ near the river.
A. playing B. to be playing C. play D. to play
答案A. 本题强调其动作，正在河边玩，应此用see sb. doing sth句型。
独立主格
（一）： 独立主格结构的构成：
名词(代词)+现在分词、过去分词； 名词(代词)+形容词； 名词(代词)+副词； 名词(代词)+不定式； 名词(代词) +介词短语构成。
（二）独立主格结构的特点：
1）独立主格结构的逻辑主语与句子的主语不同，它独立存在。
2）名词或代词与后面的分词，形容词，副词，不定 式，介词等是主谓关系。
3）独立主格结构一般有逗号与主句分开。
举例：
he test finished, we began our holiday.
= When the test was finished, we began our holiday.
考试结束了，我们开始放假。
The president assassinated, the whole country was in deep sorrow.
= After the president was assassinated, the whole country was in deep sorrow.
总统被谋杀了，举国上下沉浸在悲哀之中。
Weather permitting, we are going to visit you tomorrow.
如果天气允许，我们明天去看你。
This done, we went home.
工作完成后，我们才回家。
The meeting gone over, everyone tired to go home earlier.
会议结束后，每个人都想早点回家。
