'While' and 'as' are used to describe actions that occur at the same moment that something is in progress. 'While' and 'as' are sometimes confused with the preposition 'during'. Both express the same idea, however, the structures are different. 'While' and 'as' are time expressions and take a subject and verb. 'During' is a preposition and is used with a noun or noun phrase. Take a look at the following examples to note the difference.

　　“while”和“as”用来描述在同一时间正在进行的事。"While”和“as”有时会与介词“during”混淆。两者都表达了同样的意思，然而，结构却不同。"While”和“as”是用来表达时间，有主语和谓语动词。“During”是一个介词，和名词或名词短语连用。看看下面的例子来分清差异。

　　Notice how the meaning remains the same in both structures:

　　注意在两种结构中，它们的含义如何保持相同：

　　Examples - During:

　　During的例句

　　We discussed the situation during lunch. (noun)

　　我们在午餐时讨论了一下情况。(名词)

　　They are going to visit the Empire State Building during their visit to New York (noun phrase).

　　他们将在访问纽约期间参观帝国大厦(名词短语)。

　　The following sentences can also be expressed using the time expressions 'while' or 'as'. Be sure to take careful note of how the structure changes.

　　下面的句子也可以用表示时间的‘while’或‘as’来表达。一定要注意它们结构的变化。

　　Examples - When / As:

　　When/As的例子：

　　We discussed the situation while we were eating lunch. (full adverb time clause with subject and verb)

　　我们在吃午饭的时候讨论了情况。(主谓齐全的时间状语从句)

　　They are going to visit the Empire State Building as they visit New York. (full adverb time clause with subject and verb)

　　他们将在参观纽约时参观帝国大厦。(主谓齐全的时间状语从句)

　　Future: Use 'while' or 'as' to state something that occurs at the same moment that something else - the main focus of the sentence - important will occur.

　　将来时态：使用“While”或“as”来表示某事和另一件事同时发生，另一件事重要的事即句子的焦点。

　　Time clause: present simple

　　时间从句：一般现在时

　　Main clause: future form

　　主句：一般将来时

　　Examples:

　　例子：

　　We're going to speak about the modifications as you eat lunch.

　　当你吃午饭的时候，我们谈谈修改的内容。

　　She'll work out the order details while we discuss what to do next.

　　当我们讨论下一步该怎么做时，她会整理出订单的细节。

　　Present: Use 'while' or 'as' to express what always happens when something else important takes place. This use of 'while' and 'as' is not as common as the time expression 'when'. Notice that the preposition 'during' is often used in place of 'while' or 'as' to express the same idea.

　　现在时：用“while”或“as”来表达当其他重要事情发生时，一直发生的事情。“while”和“as”的这种用法不像表达时间的“when”那么普遍。介词“during”经常用来代替“while”或“as”来表达相同的意思。

　　Time clause: present simple

　　时间从句：一般现在时

　　Main clause: present simple

　　主句：一般现在时

　　Examples:

　　例子：

　　He usually has lunch while he take a walk around the campus.

　　他经常在校园里散步的时候吃午饭。

　　Angela often takes notes as the meeting progresses.

　　安吉拉经常在会议进行的时候做笔记。

　　Past: 'While' and 'as' are used in the past to express an action that was occurring at the moment when something important happened. 'While' and 'as' are also used to express two actions that were happening at the same moment in the past.

　　一般过去时：“While”和“as”用在过去时中用来表示当重要的事情发生时，正在发生的动作。“While”和“as”也用来表示过去发生在同一时刻的两种行为。

　　Time clause: past simple OR past continuous

　　时间从句：一般过去时或过去进行时

　　Main clause: past simple OR past continuous

　　主句：一般过去时或过去进行时

　　Examples:

　　例句：

　　Doug was drying the dishes while we were watching TV.

　　我们在看电视的时候，道格正在烘干盘子。

　　Peter took notes as we discussed the merger.

　　彼得在我们讨论合并的时候做了笔记。

　　As Long As / So Long As = During an Entire Period of Time

　　'As long as', and 'so long as' are similar in use to 'while' and 'as'. However, 'as / so long as' is used for longer period of times, while 'when' and 'as' are used for more specific, shorter periods of time. 'As / so long as' are also used to stress that something will happen, happens or happened over the entire period of time in an emphatic manner. Although examples are provided for the past, present and future, 'as long as' and 'so long as' are generally used with future forms. Notice the use of tenses:

　　“As long as”和“so long as”的用法类似于“while”和“as”。然而，“as/so long as”用于更长的时间，而“when”和“as”用于更具体、更短的时间。“as / so long as”也用来加强语气表达过去发生，正在发生或将要发生的事。虽然提供了过去、现在和未来的例句，但“as long as”和“so long as”通常用于将来形式。注意时态的用法：

　　Future: Use 'so / as long as' that something will not happen for the entire period of time expressed by the time clause with 'as / so long as'.

　　将来时态：使用“so/as long as”来表达在这段时间内(不)会发生的事。

　　Time clause: present simple

　　时间从句：一般现在时

　　Main clause: future form

　　主句：将来形式

　　Examples:

　　例句：

　　I will never play golf as long as I live.

　　只要我活着，我就永远不打高尔夫球。

　　She will never return so long as she goes out.

　　只要她走了，她就不会再回头。

　　Present: Use 'as / so long as' to express that something happens or doesn't happen over the entire period of time that another event occurs.

　　现在时态：使用“as/so long as”来表示在另一个事件发生的整个时间段内某事发生了或不会发生。

　　Time clause: present simple

　　时间从句：一般现在时

　　Main clause: present simple

　　主句：一般现在时

　　Examples:

　　例句：

　　As long as he plays the piano, I go for a walk.

　　只要他弹钢琴，我就去散步。

　　She visits him every month, so long as her husband has to take care of business in town.

　　只要她丈夫在镇上做生意，她就每个月去看他一次。

　　Past: Use 'as / so long as' to describe an action that did or didn't occur over a longer period of time in the past.

　　过去时态：用“as/so long as”来描述过去或更长时间内做过或没有发生过的行为。

　　Time clause: past simple

　　时间从句：一般过去时

　　Main clause: past simple OR past continuous

　　主句：一般过去时或过去进行时

　　Examples:

　　例句：

　　She didn't get any exercise as long as she was working 60 hours a week.

　　只要她每周工作60小时，她就没有运动。

　　Peter didn't enjoy his work so long as he was in the house.

　　只要他在家里，彼得就没法开心地工作。