Unit 4 Astronomy：The science of the stars
⑤we of/from our hotel at 5 a.m. to catch a 7 a.m. flight.
答案：①gave out②pick; out③come out ④turned out⑤checked out
13. what it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe.
隨后它會變成什么沒人能知道，直到38~45 億年前，這團塵埃才慢慢地形成一個固體的球狀物。
what it was to become ...是what 引導的主語從句，what 在從句中作become 的賓語。
what surprised everybody was that he didn’t come to the meeting.
使大家驚奇的是他竟沒有參加會議。
what he did added to our difficulty.
他所做的增加了我們的困難。
“be+動詞不定式”在本句中表示按照計劃、安排將要發(fā)生的動作。
when are they to hand in their plan?
他們的計劃什么時候交上來？
you are to do your homework before you watch tv.
你得做完了作業(yè)才能看電視。
聯(lián)想拓展
“be+to”還可以表示以下含義：
表示可能性，相當于can,主要用于疑問句和否定句。表示命令，意為“必須，不得不”，意思等同于must, have to，表示假設。表示“命運注定……”，通常用于過去時。
how am i to know what has become of him?
我怎么知道他的遭遇如何呢？
certain skills must be learned if one is to use english well.
如果想要用好英語，某些技巧是必須學的。
he was never to see his wife again.
他注定再也見不到他妻子了。
were we to offer you more money, would you stay?
如果我們給你加錢，你愿意留下嗎？
高手過招
單項填空
in dry weather the flowers will have to be watered if they . （原創(chuàng)）
a. have survived b. are to survive
c. would survive d. will survive
解析:選b。考查真實條件句。are to survive在此處并不表示將來，而表示“期望”。
14. but when i tried to step forward, i found i was carried twice as far as on the earth and fell over.
而當我試著向前邁步的時候，我發(fā)覺我被送出去很遠，步子的跨度竟是地球上的兩倍，因而我摔倒了。
twice as ...as ... 是……的兩倍
聯(lián)想拓展
英語中的倍數(shù)表達法：
倍數(shù)+as +adj./adv.+as 是……的幾倍
倍數(shù)+adj./adv.的比較級+ than 比……(多/大)幾倍
倍數(shù)+ the +表示長度/高度/寬度等的名詞+ of是……長度/高度/寬度的幾倍，此結(jié)構(gòu)中常用的名詞有：size, height, weight, length, width, depth等。