Unit4 big business-grammar學(xué)案
unit4 big business-grammar學(xué)案一.快捷識記
i. 過去分詞作狀語所表示的意義：
過去分詞短語作狀語，可表示時間，原因，條件等，可發(fā)展為一個狀語從句。過去分詞作狀語可分為：
一般式 (done) 表示分詞動作與謂語動作同時發(fā)生或分詞動作發(fā)生于謂語動作之前。
完成式 (having been done) 強調(diào)分詞動作發(fā)生在謂語動作之前。例如：
scolded (as she was scolded) by the teacher, the girl sat there without lifting her head.
由于被老師批評了，那個女孩低著頭坐在那兒。
ii.過去分詞作狀語時的具體用法：
1.過去分詞作時間狀語相當(dāng)于一個時間狀語從句。例如：
asked (when he was asked) what had happened, he lowered his head.
當(dāng)他被問問題的時候,他低下了頭。
2.過去分詞作原因狀語相當(dāng)于一個原因狀語從句。例如：
frightened (=because / as she was frightened) by the tiger, the girl didn't dare to sleep alone.
因為害怕老虎, 這個女孩不敢單獨睡覺。
3.過去分詞作條件狀語相當(dāng)于一個條件狀語從句。例如：
grown (if these seeds are grown) in rich soil, these seeds can grow fast.
如果種在肥沃的土壤里， 這些種子能長得很快。
given (if we were given) more time, we could do it better.
如果給我們更多時間的話，我們可以做得更好。
注意：此句中的given在許多語法書中作為介詞處理。
4.過去分詞作讓步狀語相當(dāng)于一個讓步狀語從句。例如：
left (although he was left) at home, john didn't feel afraid at all.
雖然john被單獨留在房間里, 他一點都不害怕。
5. 過去分詞作狀語表示伴隨動作或狀態(tài)。例如：
the teacher entered the classroom, (and he was) followed by a group of students.
老師進入教室，后面跟著一幫學(xué)生。
二. 練一練：
1. ________ in the queue for half an hour, tom suddenly realized that he had left his wallet at home.
a. to wait b. have waited
c. having waited d. to have waited
2. ________ by the beauty of nature, the girl from london decided to spend another two days on the farm.
a. attracting b. attracted
c. to be attracted d. having attracted
3. the research is so designed that once ________ nothing can be done to change it.
a. begins b. having begun
c. beginning d. begun
4. ________ to sunlight for too much time will do harm to one's skin.