狀語從句的語法-

狀語從句包括時間、地點、原因、條件、讓步、方式、比較、目的和結果等幾類。

1. 時間狀語從句

1）as soon as, the moment, immediately, the minute, the second, the instant, every time等連詞引導的時間狀語從句表示“一…就” , “每次”。

She came to the scene the moment she heard of the accident.

Every time I came to see Mr. Johnson, he is always working on his project.

2）Hardly/ Scarcely… when…; No sooner … than…引導的時間狀語從句表示“一…就…”；“剛…就…”。主句要用過去完成時，hardly, scarcely, no sooner 位于句首時，句子要倒裝。例：

Hardly had I left my house than it rained.   

No sooner had I  finished my homework than the power failure came.  

         3）when , while, whenever

              When: 某一時刻, 可接延續動詞或短暫性動詞。

                  e.g: I’ll speak to him when he arrives.

                     The doorbell rang when I was telephoning.
             While: 相當于during that time, 表示一個時間段，故一般只接延續動詞.

                           e.g: I was walking along the road while suddenly someone patted me on the shoulder from behind. 

             Whenever: 無論何時

                          e.g: Whenever you say “I love you”, mean it.       

                               Whenever you say “I’m sorry”, look the person right in the eyes.

2. 條件狀語從句中

1） if 和unless       if 表示正面的條件，意為“如果”；unless意為“除非，如果不”＝if… not

       You will not be allowed to go into the room unless you show your ticket.

2) as/so long as, on condition that, suppose/ supposing(that), in case (of).., provided that都有“如果，只要，假如，在…條件下”。例：

Suppose/ Supposing (that) we only have three days to live, what shall we do?

In case of fire, ring the alarm bell.

3. 在時間和條件狀語從句中，用一般現在時代替將來時。

       We will have an outing if it is fine tomorrow.

4. because, since, as 都可引導原狀語從句，because 的語氣最強，常用于回答以why 引導的疑問句。Since 表示一種附帶的原因，或表示已知的、明顯的理由，意為“既然”。As表示的理由最弱，只是對主句的附帶說明，重在主句。例：

            Because she was late for more than half an hour, she was not allowed to take part in the exam.

       Since everybody is here, let’s start the meeting

       As I am about to start a journey, I shall not be able to begin the work before I return.

l   注意：because, since, as不可與so連用

 

5 since 和now that 意義相近， 意為“既然”，“鑒于” ，有時省去that 也可表示原因狀語。e.g：Now（that）you are old enough to make your own judgment, you should start your own career.

6. in that引導原因狀語從句，意為“（原因）就在于”。例

              Theory is valuable in that it can provide a direction for practice.

7．Though, although, even if, even though, as whether…or(not) 可引導讓步因狀語從句。

       1） though, although 不可與but 連用。

       2） though引導的讓步狀語從句可倒裝。

             Though he was young, he faced the difficult situation calmly.

               = Young as he was, he faced the difficult situation calmly.

       3)  whether …or (not) 引導讓步因狀語從句,提供兩個對比的情況，意為“不管…”

              Whether it rains or not, I shall go out for an outing tomorrow.