感官動詞 see,watch,observe,notice,look at,hear,listen to,smell,taste,feel + do 表示動作的完整性,真實性；+doing 表示動作的連續(xù)性,進行性
I saw him work in the garden yesterday.
昨天我看見他在花園里干活了.(強調"我看見了"這個事實)
I saw him working in the garden yesterday.（強調"我見他正干活"這個動作）
昨天我見他正在花園里干活.
典型例題
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.因題意為,他們看著她長大,因此強調的是成長的過程,而非正在長的動作,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.本題強調其動作,正在河邊玩,應此用see sb.doing sth句型.