獨(dú)立主格結(jié)構(gòu)主要表示謂語(yǔ)動(dòng)詞發(fā)生的時(shí)間、原因、條件或伴隨情況等，相當(dāng)于一個(gè)狀語(yǔ)從句或并列句。??????

1. 用作時(shí)間狀語(yǔ)The work done (=After the work had been done), we went home. 工作完成后，我們就回家了。2. 用作條件狀語(yǔ)Weather permitting (=If weather permits), they will go on an outing to the beach tomorrow. 如果天氣允許的話(huà)，他們將在明天組織一次海濱小游。3. 用作原因狀語(yǔ)An important lecture to be given tomorrow (=As an important lecture will be given tomorrow), the professor has to stay up late into the night. 因?yàn)槊魈煲l(fā)表一個(gè)重要的演講，教授不得不熬夜到很晚。4. 用作伴隨狀語(yǔ)He was lying on the grass, his hands crossed under his head (=and his hands were crossed under his head).他躺在草地上，兩手交叉枕在腦后。
　　
表示補(bǔ)充說(shuō)明一個(gè)獵人走了進(jìn)來(lái)，他的臉凍得通紅We redoubled our efforts, each man working like two. 我們加倍努力，一個(gè)人干兩個(gè)人的活。注：獨(dú)立主格結(jié)構(gòu)表示時(shí)間、條件或原因時(shí)，相當(dāng)于一個(gè)狀語(yǔ)從句，一般放在句首，表示原因時(shí)還可放在句末；表伴隨狀況或補(bǔ)充說(shuō)明時(shí)，相當(dāng)于一個(gè)并列句，通常放于句末。