Units 15～16 The necklaceScientists at work Ⅰ.单项填空1．I can never forget one afternoon ten years ago________you came to my house and helped me out of trouble.A．while B．when C．that D．where 答案：B2．More natural resources should be________use of to meet the increasing need of energy.A．put B．brought C．taken D．made解析：此是 make use of 短语的被动语态形式。答案：D3 ． I told you that you shouldn’t waste your time playing football all day long ，________？A．didn’t I B．did I C．should you D．shouldn’t you解析：反意疑问句通常要与主句的主语和谓语一致。此句意为“我没告诉过你吗？”答案：A4．This material________，so be careful when you wear it.A．is torn easily B．is torn easy C．tears easily D．tears easy解析：tear“破裂，撕破”，可用作不及物动词，后跟一副词，表示某东西的特性。 答案：C5．________existed a certain doubt among the workers as to the necessity of the work.A．It B．There C．What D．That解析：表示“对……有疑虑”要用 there is/exists a doubt 句式。答案：B6．It took Mary a long time to________a new dress at the store.A．pick up B．pick out C．take up D．take out解析：pick up“捡起”；pick out“挑出”；take up“从事于”；take out“拿出”。答案：B7．These colors won’t________if exposed to the sun.A．last B．hold C．keep D．insist解析：last 作不及物动词，意为“持续，耐久”。其他三个词均无此用法。答案：A 8 ． There were also a gun and a thin piece of rope with the end________in a circle.A．being tied B．tying C．to be tied D．tied用心 爱心 专心1解析：with 后可接复合结构，且 end 与 tie 是被动关系，故用过去分词。答案：D9 ． A line of forts was built along the border to________the country against attack.A．prevent B．support C．protect D．control解析：protect...from/against...“保护……免于……”。答案：C10．A cup of hot milk on a cold night is________.A．re...
