题目内容
下列基团在芳环取代反应中定间位的是（ ）。a. —CH3 b. —OH c. —NO2 d. —COCH3
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什么是构象和构型？举例说明。
Section DDirections: In this section you will hear a recorded short passage. The passage is printed in the test paper, but with some words or phrases missing. The passage will be read three times. During the second reading, you are required to put the missing words or phrases on the Answer Sheet in order of the numbered blanks according to what you hear. The third reading is for you to check your writing. Now the passage will begin.John is a bus driver. He gets up at six o’clock, eats a light (16) in a hurry, and then rushes to work. He likes his job but hates to drive in bad (17) . Rain and snow make the roads dangerous.John’s wife, Carol, works every day from (18) to noon as a bookkeeper. She likes keeping her house neat and tidy. She has a place for everything and throws out what she doesn’t need. John is just the opposite. He (19) everything. He keeps clothes that don’t (20) him any more, old magazines, boxes and papers. Nothing of his is in good order.
SectionA:Directions:Thissectionistotestyourabilitytogiveproperresponses.Thereare5recordedquestionsinit.Aftereachquestion,thereisapause.Thequestionswillbespokentwotimes.Whenyouhearaquestion,youshoulddecideonthecorrectanswerfromthe4choicesmarkedA),B),C)andD).
Thissectionistotestyourabilitytogiveproperresponses.
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