【正文】 Sterling may fall, if (this should be) so, interest rates will rise. 英國貨幣可能貶值，如果果真如此，利率就會上升。 If it is fine tomorrow, we could go out. 如果明天天氣好，我門能夠出門。 If it is fine tomorrow, we ought to go out. 如果明天天氣好，我門宜于出門。用 should 起始句子即可不用 if 而表示條件。 9 If you should happen to see him, please give him my regards. 如果你萬一見到他，請代我向他致意。 Should you be interested in our offer, please contact us. 你若對我們的報價感興趣，請與我們聯(lián)系。 should 可以提前，而將 if 省略。 If it should rain, our plan would be spoiled. 萬一下雨，我們的計劃就泡湯了。 If I were to be born again, I would like to be a bird. 我要是再活一次，我想當(dāng)一只鳥。 If I knew his address, I could write to him. 如果我知道他的住址，我會寫信給他。 If I had a car, I could take her for a drive. 如果我有車， 我就帶她去兜風(fēng)了。 that 子句 也能用 to 不定詞 來表示。 It is high time he should e to our house for 該上咱家吃晚飯的時候了。 if 子句 中的 had 可置于 主詞 前面，而省略 If。 I someone had been with him, he might not have been drowned. 如果有人在他旁邊，或許他就不會溺死。 Had I proposed to you, would you have married me? 我要是當(dāng)年向你求婚，你會答應(yīng)嫁給 我嗎 ? Had you not helped us, we should have canceled this transaction. 假如沒有你的幫助，這筆生意早就告吹了。 If he had worked harder when young, he would be well off now. 如果他年輕時多努力一點，現(xiàn)在就能過得舒服些。 I wish ... + Ved ... 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶I wish＋（ that）＋主詞＋動詞過去式／過去完成式（ had＋過去分詞） ? 說明 ∶ 說明 ∶I wish 之后以 that 子句 為 受詞 時，該 子句 的 動詞 一定要用 假設(shè)語氣 ：若 動詞 用過去 式， 表示與現(xiàn) 在事實相反的愿望； 若用 過去完成式 ， 則表示與過去事實相反的愿望。 11 I wish I were as tall as you. 但愿我像你一樣高。 I wish you had not told the truth. 但愿你沒有說實話。 If only I had a rich father. 要是我有個有錢的爸爸就好了。 as if， as though 是 副詞 連接詞 ，引導(dǎo) 副詞子句 。 He felt as if he almost wished to kill them. 他感覺彷佛幾乎要殺掉他們。 She looks as if nothing had happened to her. 她當(dāng)時看起來好像什么事都沒發(fā)生似的。 It seems as if he knows everything. 他似乎是個萬事通。 It seemed as if he had finished the work. 他似乎已經(jīng)完成了這個工作。亦可用 “but for ＋ 名詞 ” 或 “without ＋ 名詞 ” 代替。 But for music (=Were it not for music), life would be dull. 要不是音樂，人生會很無聊。 I should be lonely, were it not for the birds and the flowers. 我會寂寞，若非有鳥也有花。此類句構(gòu)專門用于表示與過去事實相反的 假設(shè)語氣 。 Had it not been for the kind guide, I might have got lost in the mountains. 要不是這位好心的向?qū)В铱赡芫驮谏街忻月妨恕? 美式英語通常省略 should。 They ruled that the law (should) not be imposed. 他們規(guī)定不應(yīng)加重法律。 Recently, many states have insisted that high schools teach students how to drive. 最近，許多州堅持中學(xué)應(yīng)該教學(xué)生如何開車。 It is necessary that he (should) sort out the information for my reference. 他有必要整理些資料供我參考。 It is important that he be quiet. 他該保持安靜是有必要的。 Imperative Sentence + Conj. + Main Clause 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶ 祈使句＋連接詞＋主句 說明 ∶ 說明 ∶ 祈使句 表示須具備的條件，主句表示可能的結(jié)果。 Stop shouting or you’ll wake up the neighbors. 不要喊了，否則你會 把鄰居吵醒的。 Stop eating sweets, or you won’t get any dinner. 你如果 不停止吃糖，你就不要吃飯。 Unless you change your mind (=If you don’t change you mind), I won’t be able to help you. 除非你 改變你的想法，否則我不能幫助你。 Provided/Providing (that) 引導(dǎo)假設(shè)條件句，其功能相當(dāng)于 if。 So (As) long as you。 As/So long as ... 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶As/So long as ＋子句， S＋ V ... 說明 ∶ 說明 ∶ 此句型意為“ 如果 ? ，只要 ?” 。 I couldn’t have got to the meeting on time － unless I had caught an earlier train. 我不可能及時趕到會場，除非我趕上了較找的一班火車。 unless 引導(dǎo)一個否定假設(shè)句，相當(dāng)于 if ... not ...，有時可以互換使用。 Be there on time, otherwise you’ll create a bad impression. 要準(zhǔn)時來，否則你會給人一個壞的印象。 祈使句 的用法比 if 子句表示的更為緊迫。 It is requested that all members be present at the party. 全體會員都被要求出席這次晚會。 It is urgent that food and clothing (should) be sent to the sufferers. 急需將食物和衣服送給災(zāi)民。 It is proper ... that ... 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶It is＋意志形容詞（ important 等）＋（ that）＋主詞＋（ should）＋原形動詞 說明 ∶ necessary ， imperative， essential， urgent， desirable， advisable， 說明 ∶ 意志 形容詞 包括 important， remendable， proper 等。 My mother encouraged me and insisted that I continue my education. 我媽媽鼓勵我，而且堅持我應(yīng)該繼續(xù)我的教育。 His parents demanded that he (should) be back by ten. 他的父母要求他十點以前回家。 I demand/insist that ... 結(jié)構(gòu) ∶ 主詞 1＋意志動詞（ demand／ insist 等）＋（ that）＋主詞 2＋（ should）＋原形動詞 結(jié)構(gòu) ∶ 說明 ∶ ，要求（ desire， 說明 ∶ 意志 動詞 有四類：建議（ suggest， remend， propose， advise， urge 等） ask，demand， require， request， maintain， insist 等） ，命令（ order，mand 等） ，規(guī)定（ rule， regulate， stipulate 等） 。 Had it not been for your timely help, our pany would have been on the verge of bankruptcy. 若非你及時伸出援助之手，本公司將會瀕臨破產(chǎn)的邊緣。 Were it not for science, we could not live a fortable live. 若非科學(xué)，我們無法過著舒適的生活。 Without air, all living things would die. 若非空氣，所有的生物都會死亡。 If it were not for his presence, I would punish you. 要不是他在場，我會處罰你的。 If it were not for ... 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶if it were not for ＋名詞／子句，主詞＋ would／ should 等＋原形動詞 ? 說明 ∶ 說明 ∶ 此句型意為 “ 若非（有） ?” 。其實他是再愚蠢不過了。本句型中的 as if 子句 可用以表示事實，或 假設(shè)語氣 。 The nurse attends on the patient as if he were her father. 這護士照顧這位病人彷佛在照顧她爸爸似的。 He speaks like that as if he doesn’t want to attend the meeting. 他那樣說話，似乎不想?yún)⒓訒h。 If only I had another chance. 要是我再有一次機會就好了。 If only + Ved 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶If only ＋過去式／過去完成式 說明 ∶ 此句型意為 “ 要是 ? 就好了。 I wish (=I would rather) he could e tomorrow. 但愿他明天能來。而 I hope 之后以 that 子句 做 受詞 時，該 子 句 用一般 時態(tài) 。 Had he told the truth, he wouldn’t be punished now.如果他當(dāng)時肯說實話，現(xiàn)在就不會受罪了。即： if 子句 若與過去事實相反，用 過 去完成式 表示；而 主要子句 若與現(xiàn)在事實相反，則用過去式 助動詞 表示。 Had he not apologize to her, she would not have fiven him. 她（那時）不會原諒他，若非他道了歉。 I could have finished the task if I had had more time. 如果當(dāng) 時我能有多一點時間，我就能完成這項任務(wù)。 If I had Ved, I would have ... 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶If?had ＋過去分詞 ? ，主詞＋ would／ should 等＋ have＋過去分詞 說明 ∶ 說明 ∶ 這是與過去 事實相反的假設(shè) 句型 。 It is time that you left for the duty. 該你當(dāng)班了。 It is time that ... 結(jié)構(gòu) ∶ 結(jié)構(gòu) ∶It is （ high） time＋（ that）＋主詞＋過去式動詞 10 說明 ∶ 說明 ∶ 此句型意為 “ 已經(jīng)到了 ? 的時間了 ” 。 If you were in my shoes (=Were you in my shoes), what would you do? 如果你站在我的立場，你會怎么做？ Were I rich enough, I would buy a sports car. 如果我有足夠的錢，我就買一輛賽車了。 if 子句 中的 be動詞 ，不論 主詞 為第幾人稱，一律用 were， were 可置于主詞前面，而省略 if。 Should another world war break out, what would bee of human beings? 萬一另一次世界大戰(zhàn)爆發(fā)，人類將會發(fā)生什么事？ If I were to