因?yàn)橛⒄Z(yǔ)講究一個(gè)金字塔結(jié)構(gòu)（無(wú)論是句子還是段落）,頭要小,腳要重.所以當(dāng)句子的主語(yǔ)或者主語(yǔ)部分過(guò)重（就是指字太多）時(shí),我們就引入一個(gè)邏輯主語(yǔ)（it）放在句首充當(dāng)主語(yǔ),而真正的主語(yǔ)就可以用不定式（to do sth）放在句子后面 例如 It is important for us to study English well it就是邏輯主語(yǔ) to study English well 就是真正的主語(yǔ) 所以翻譯起來(lái)就是 學(xué)好英語(yǔ)對(duì)于我們很重要 其實(shí)就是 TO stydy English well is important for us.伴隨狀語(yǔ)是指狀語(yǔ)從句的動(dòng)作伴隨主句謂語(yǔ)一同發(fā)生.它的特點(diǎn)是：它所表達(dá)的動(dòng)作或狀態(tài)是伴隨著主句謂語(yǔ)動(dòng)詞的動(dòng)作而發(fā)生或存在的.伴隨狀語(yǔ)出現(xiàn)的條件是：1、一個(gè)主語(yǔ)同時(shí)發(fā)出兩個(gè)動(dòng)作 2、同一個(gè)主語(yǔ)處于兩種狀態(tài),3、或一個(gè)主語(yǔ)發(fā)出一個(gè)動(dòng)作時(shí)又伴隨有某一種狀態(tài).伴隨狀語(yǔ)的邏輯主語(yǔ)一般情況下必須是全句的主語(yǔ),伴隨狀語(yǔ)與謂語(yǔ)動(dòng)詞所表示的動(dòng)作或狀態(tài)是同時(shí)發(fā)生的.伴隨狀語(yǔ)可以有以下幾種表示方法：一、使用分詞形式 The dog entered the room,following his master(這條狗跟著主人進(jìn)了屋).The master entered the room,followed by his dog(主人進(jìn)了屋,后面跟著他的狗).二、用with復(fù)合結(jié)構(gòu) The little girls were playing with snow with their hands frozen red(小女孩們?cè)谕嫜?手都凍紅了).The workers went out of work,talking and laughing all the way(工人們下班了,一路有說(shuō)有笑).三、用獨(dú)立主格結(jié)構(gòu) Last year I came here by climbing over the wall,sword in hand.The little boy goes to school,the little dog accompanying him every day(這小孩每天去上學(xué),那條小狗陪伴著他).四、用形容詞 Crusoe went home,full of fear(克魯索滿懷恐懼地回家).Confident of the victory the players are fighting hard(運(yùn)動(dòng)員們對(duì)比賽奪勝滿懷信心奮力拼搏).The match will be broadcast live(這場(chǎng)比賽將作實(shí)況轉(zhuǎn)播).He left home young and came back old(他少小離家老大回).五、用名詞 He went away a beggar but retumed a millionaire(他討吃要飯離家,腰纏萬(wàn)貫回歸).He who had been twice prime minister of the country,died civilian(他曾兩度出任這個(gè)國(guó)家的總理,而死的時(shí)候卻是一個(gè)平民).六、用介詞短語(yǔ) The girl came back to her mother in tears.(這女孩眼淚汪汪地回到母親身邊).How can you go to the wedding party in rags(你怎能衣衫襤褸地去參加婚宴)?I went home out of breath(我上氣不接下氣地回家).