有,
but是并列連詞,yet屬于副詞
but一般是在句子的開始部分,而yet是用于句尾的
but是用語肯定句中,yet用語否定句或疑問句中
一、副詞 yet 作“還”,“仍然”講
1.Much yet remains to be done.尚有許多事情待做.
2.Yet molecules are always moving,some perhaps as fast as a mile per second.
分子仍然總在運(yùn)動(dòng),其中有些分子的運(yùn)動(dòng)速度達(dá)每秒一英里.
3.The experiment is not yet over.這項(xiàng)試驗(yàn)尚未結(jié)束.
4.No one has yet seen an electron.還沒人見過電子.
5.Man has not yet learned to store the sun's heat.人類尚未學(xué)會(huì)貯藏太陽熱.
二、副詞 yet 和比較級(jí)連用,作“還要”,“更”講,?？捎?even 代替
1.This is a yet ( 或 even) more difficult task.這是一項(xiàng)更為艱巨的任務(wù).
2.We must study yet ( 或 even) harder.我們必須更加努力學(xué)習(xí).
三、副詞 yet 用于現(xiàn)在完成時(shí)作“已經(jīng)”講,只用于否定句和疑問句中
1.Have you seen such a space shuttle yet?你（已）見過這樣的航天飛機(jī)嗎?
2.Has the bell rung yet?鈴已打過了嗎?
3.The bell has not been repaired yet.鈴尚未修好.
注：在肯定句中表示“已經(jīng)”要用 already,不能用 yet.若在疑問句中用 already 代替 yet,則表示驚異的語氣.
eg:Has the bell rung already?鈴真的打過了嗎?
四、連詞 yet 和 and yet,but yet 用法舉例
1.It is very good,yet ( 或 but) it can be better.這很好,但還能精益求精.
2.It is strange,and yet it is true.( =It is strange yet ( 或 but) true.) 真奇怪,卻是真的.
3.Air has weight,and yet it is very light.空氣有重量,雖然很輕.
4.Although this matter sounds strange,yet it is true.此事聽起來雖然奇怪,但卻是事實(shí).
5.The wheel is the simplest yet ( 或 but) perhaps the most remarkable of all inventions.
輪子是所有發(fā)明中最簡(jiǎn)單卻也許是最非凡的一種.
6.Everyone thinks that this is a simple method,(but) yet he cannot believe it.
大家都認(rèn)為只是個(gè)簡(jiǎn)單方法,但他不信.
五、詞組 as yet （到目前為止）和 just yet （就在此刻）常用于否定句中
1.They have not made such an advanced computer as yet.
他們目前尚未制造出這樣一種先進(jìn)的計(jì)算機(jī).
2.No one has as yet been able to produce the absolute zero of temperature.
還沒有人能產(chǎn)生絕對(duì)零度.
3.It will not happen just yet.此事一時(shí)尚不至于發(fā)生.
but
prep.除...以外
conj.而是,但是
adv.幾乎,僅僅
辛苦中.大哥,這是初中知識(shí)好象.俺就是初中生.