一些英語單詞用法問題,
1.Since & as 的區別：
老師說since是“由於”的意思,as是“眾所周知”的意思,除since是現在完成時標誌外,兩者的明顯區別是什麼?
我記得看過這樣一種句型,是把as放句子中間後面再加一個句子的,請問是什麼句型?
（曾經做過這樣一道題目：
---Why didn’t you go to school yesterday?
---_____________my mother is ill,I had to look after her at home.
當時填的是“since”,老師說正確答案應該是“because”,請問,是否所有用“why”提問的句子,都應用“because”回答?什麼情況下,可以用“since”或是“as”回答問題?）
2.however & but & while 的區別：
While有“然而”的意思,錶轉折.但是“however”也表“然而”,“but”也錶轉折,同（1）,三者的區別是什麼?（所用於的句型、程度大小……）
一、除because,as,since外,還有for ,這四個詞作為連詞,都有"因為"的意思,但它們在用法上有區別：
because 是從屬連詞,接表示直接原因的從句,一般放在主句的後面,也可放在主句前面,它表示的語氣最強,在回答why的問句時,必須用because.
例如：The swimming pool won"t be open today because they"re making repairs.
游泳池今天不開放,因為他們在修理.
Why did you move to France?
你們為什麼搬到法國?
Because my father found work in Paris.
因為我父親在巴黎找到了工作.
注意：在英語中用了because後,不可再用so.
as 是從屬連詞,說明一般的因果關係,語氣比because弱,說明比較明顯的原因,它引導的從句通常放在句首,有時也可放在句末.
例如：As it is raining, you\"d better take a taxi.
天下雨了,你最好乘計程車.
since 意為"既然",表示對方已知的無需加以說明的原因或事實,語氣比because弱,但是比as 強.
例如：Since we have no money, we can"t buy that vase.
既然我們沒錢,我們就不能買那花瓶.
Since everybody is here, let"s begin our party.
既然大家都到了,那就開始我們的聚會吧!
for 是並列連詞,用來附帶解釋說明前一分句的原因或理由,for引導的並列句,一般放在所要說明的句子的後面.
例如：I went to see him, for I had something to tell him.
我去見他,因為我有事要告訴他.
二、however & but & while 的區別
1, "while"著重強調前後兩者對比,如"Tom is reading while Jim playing football.
當吉姆在玩足球的時候,湯姆正在讀書",
"i am doing homework while you are sleeping,
當你在睡覺的時候,我正在做家庭作業"
2,"But"著重強調前後意思轉折,並且轉折的語氣最為強烈,用的最多,
i really want to go shopping with you,but i do have no money
我是真的很想和你一起購物,但是我身上確實沒啊
you can jion us in this game,but you must comply with rules of the game
你可以加入我們,但是你必須遵守遊戲規則".
3,"however"的
用法很簡單,一般放在兩句之間,前後用逗號隔開獨立成句,表示意思的轉折,譯為"然而、不過",
you should finish your work before nine o"clock, however, you can have a break before you start it
你應該在9點之前完成你的工作,不過在開始之前你可以稍做休息
I asked uncle LI for more money,however, i have enough money to buy it
我問李叔叔要了更多的錢,然而我自己有足夠的錢買下它
三者的強調語氣由強到弱排列順序是：but,however,while
一些英語單詞用法問題,
1.Since & as 的區別：
老師說since是“由於”的意思,as是“眾所周知”的意思,除since是現在完成時標誌外,兩者的明顯區別是什麼?
我記得看過這樣一種句型,是把as放句子中間後面再加一個句子的,請問是什麼句型?
（曾經做過這樣一道題目：
---Why didn’t you go to school yesterday?
---_____________my mother is ill,I had to look after her at home.
當時填的是“since”,老師說正確答案應該是“because”,請問,是否所有用“why”提問的句子,都應用“because”回答?什麼情況下,可以用“since”或是“as”回答問題?）
2.however & but & while 的區別：
While有“然而”的意思,錶轉折.但是“however”也表“然而”,“but”也錶轉折,同（1）,三者的區別是什麼?（所用於的句型、程度大小……）
一、除because,as,since外,還有for ,這四個詞作為連詞,都有"因為"的意思,但它們在用法上有區別：
because 是從屬連詞,接表示直接原因的從句,一般放在主句的後面,也可放在主句前面,它表示的語氣最強,在回答why的問句時,必須用because.
例如：The swimming pool won"t be open today because they"re making repairs.
游泳池今天不開放,因為他們在修理.
Why did you move to France?
你們為什麼搬到法國?
Because my father found work in Paris.
因為我父親在巴黎找到了工作.
注意：在英語中用了because後,不可再用so.
as 是從屬連詞,說明一般的因果關係,語氣比because弱,說明比較明顯的原因,它引導的從句通常放在句首,有時也可放在句末.
例如：As it is raining, you\"d better take a taxi.
天下雨了,你最好乘計程車.
since 意為"既然",表示對方已知的無需加以說明的原因或事實,語氣比because弱,但是比as 強.
例如：Since we have no money, we can"t buy that vase.
既然我們沒錢,我們就不能買那花瓶.
Since everybody is here, let"s begin our party.
既然大家都到了,那就開始我們的聚會吧!
for 是並列連詞,用來附帶解釋說明前一分句的原因或理由,for引導的並列句,一般放在所要說明的句子的後面.
例如：I went to see him, for I had something to tell him.
我去見他,因為我有事要告訴他.
二、however & but & while 的區別
1, "while"著重強調前後兩者對比,如"Tom is reading while Jim playing football.
當吉姆在玩足球的時候,湯姆正在讀書",
"i am doing homework while you are sleeping,
當你在睡覺的時候,我正在做家庭作業"
2,"But"著重強調前後意思轉折,並且轉折的語氣最為強烈,用的最多,
i really want to go shopping with you,but i do have no money
我是真的很想和你一起購物,但是我身上確實沒啊
you can jion us in this game,but you must comply with rules of the game
你可以加入我們,但是你必須遵守遊戲規則".
3,"however"的
用法很簡單,一般放在兩句之間,前後用逗號隔開獨立成句,表示意思的轉折,譯為"然而、不過",
you should finish your work before nine o"clock, however, you can have a break before you start it
你應該在9點之前完成你的工作,不過在開始之前你可以稍做休息
I asked uncle LI for more money,however, i have enough money to buy it
我問李叔叔要了更多的錢,然而我自己有足夠的錢買下它
三者的強調語氣由強到弱排列順序是：but,however,while