．碳元素与氧元素的本质区别是

【名词&注释】

活性炭(activated carbon)、棉纤维(cotton fiber)、平衡力(balance force)、本质区别(essential difference)、支持力(supporting force)、酸碱指示剂(acid-base indicator)、上下文线索(context clues)、紫卷心菜

[单选题]．碳元素与氧元素的本质区别是

A. 质子数不同
B. 电子数不同
C. 中子数不同
D. 最外层电子数不同

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学习资料：

[单选题]下列小实验不能成功的是

A. 用食醋制无壳鸡蛋
B. 用紫卷心菜自制酸碱指示剂^{(acid-base indicator)}
C. 用活性炭将硬水软化
D. 用灼烧闻气味的方法区分棉纤维和羊毛纤维

[单选题]一个苹果静止在水平桌面上，以下说法正确的是

A. 苹果受到的重力和桌面对苹果的支持力是一对平衡力
B. 苹果对桌面的压力和桌面对苹果的支持力是一对平衡力
C. 苹果对桌面的压力就是苹果受到的重力
D. 苹果受到的重力和苹果对桌面的压力是一对平衡力

[单选题]---- Would you like some more soup?---- _______. It is delicious, but I’ve had enough.

A. Yes, please
B. No, thank you
C. Nothing more
D. I’d like some

[单选题]CManytextbooksarenotwritteninthekindofEnglishthatwespeakeveryday.Infact,sometimesthereadingisso

A. difficultthatitalmostseemslikeaforeignlanguage.Inaway,itis—thelanguageofscience.Youshouldnotexpecttobeabletoreadadifficultsciencepassagethesamewayyou
B. readaninterestingstory;youshouldnotexpecttoreaditeasilyandallatonce.Instead,youmayhavetoreaditse-
C. veraltimesthrough,catchingonthemeaningofdifficultwords,goingbackoverdifficultsentences,andfinallyputting
D. thewholethingtogether.Donotbediscouragesifthewholepassagedon’tmakesensetoyouatfirst.Youneedtopickitapartpatientlyuntilyoucanunderstandit.
E. Thesearethestepstofollowwhenyouarereadingsomethingdifficult:
F. ★1.Starttoreadnormallyuntilyourunintoasentencethatdoesn’tmakesensetoyou.
G. ★2.Whenasentencedoesn’tmakesense,gobackandreaditagainmoreslowly.
H. ★3.Lookforanywordyoudon’tknowinthesentence.Trytounderstandtheirmeaningsusingwordpartsandcontextclues(上下文线索^{(context clues)}).Ifnecessary,lookthemupinthedictionary.
I. ★4.Lookatthenextfewsentencestoseeiftheyexplainmoreaboutthesentenceyouareworkingon.Donotreadvery
J. muchfartheraheaduntilyouunderstandwhatisbeingsaid.
K. ★5.Finally,readthesentenceagain.Trytoputitintosimplerwords.
L. ★6.Readthroughthepassageonce.Trytounderstandallthehardpartswell.Thenreadthewholepassageonce
M. moreatausualspeed.Thishelpsyoutoputallidestogether.
N. Thestopssoundalotharderthantheyare.Itisreallyjustthenormalwaygoodreadersunderstandanythingthatis
O. difficulttoread.Afteryouhavedonethebestyoucanthisway,youshouldalwaysfeelfreetoaskforhelpfromyour
P. teacher,ifyouhaveone.
Q. 54.Theunderlinedphrase“runinto”means___________.
R. workout
S. comeacross
T. lookinto
U. passby

[单选题]29． There was a hole in _________．

A. his pockets
B. his left pocket
C. his right pocket
D. the wall of the garden

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