3.強調(diào)：
    強調(diào)是一種修辭方式，如前面所說的"倒裝"就是一種重要的強調(diào)手段。
    此外，還可以借助助詞進(jìn)行強調(diào)，例如：
    She did come yesterday; I saw her in the office.
    她昨天確實來了;我在辦公室見到她的。
    本講要討論的主要是"it is ….that…"強調(diào)句, 即：將句子中除謂語動詞以外的成分(主語、賓語、狀語等)用"it is ….that…"加以連接，組成強調(diào)句，如果是人，也可以用"it is… who…", 例如：
    John bought a toy train for his son yesterday.
    昨天約翰給他兒子買了輛玩具火車。
    強調(diào)主語：It was John who (或that)bought a toy train for his son yesterday.
    強調(diào)賓語：It was a toy train that John bought for his son yesterday.
    強調(diào)賓語(或目的)：It was for his son that John bought a toy train yesterday.
    強調(diào)時間狀語：It was yesterday that John bought a toy train for his son .
    學(xué)習(xí)強調(diào)句要注意以下兩點：
    不要與主語從句相混淆，例如：
    It is well known that light travels in straight lines.
    (眾所周至，光以直線傳播?！?主語從句)
    It was not until the early 18th century that the significance of the event was generally realized.
    (直到18世紀(jì)初，這一事件的意義才為公眾所認(rèn)識。——強調(diào)句)
    強調(diào)句與主語從句的簡單區(qū)分是：強調(diào)句去掉"it is…that…",句子結(jié)構(gòu)依然正確，意思不變，如上句："until the 18th century the significance of the event was not generally realized". 但是主語從句就不行，如上句："well know that light travels in straight line"就不通, 句中 "well know" 變成了無依著的成分。
    不要陷入"考試陷阱"
    例如：
    It was not until 1943 ______ Penicillin was put into clinical use that many fatal diseases were brought under control.
    A.that
    B.when
    C.before
    D.after
    看到這個題目，考生第一個反應(yīng)是"強調(diào)句"，很快選擇了A，但是再仔細(xì)讀一下，句子后面已經(jīng)有"that"，說明這個題目的考點不在"強調(diào)句"上，而是考"定語從句"的"關(guān)系副詞"when, 故正確答案是B，A稱為"干擾項".