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【简答题】
科学探究有三个要素：要有______、要有______、要有______． （1）科学探究的一般过程：______→作出假设→制定计划→______→得出结论 探究水温变化对金鱼呼吸次数的影响：在一定的温度范围内，水温升高，金鱼的呼吸次数______；水温降低，金鱼呼吸次数______． （2）科学探究实验应注意的几个问题： ①得有一个对照组，对照组的作用是______． ②实验组和对照组之间只能有______变量，两个组之间不能比较是因为变量不唯一． ③实验中经常要测量几次，对这几次的结果要取平均值，目的是______，使实验结果更准确．
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【单选题】First you board the train. Then you __________ the situation to the attendant and get a ticket.
A.
explain
B.
declare
C.
inform
D.
tell
【简答题】First you board the train. Then you explain the situation to the attendant and get a ticket.
【单选题】You board an inflatable liferaft that has been hand launched from a sinking vessel. What should you do FIRST after everyone is onboard the liferaft?
A.
Cut the painter.
B.
Operate the radio equipment.
C.
Open the equipment pack.
D.
Ventilate the liferaft of CO2.
【简答题】As a child,Alain Robert was afraid of height.One day,when he was 12,he returned home from school.At the front door of his building,he looked for his keys.He didn’t find them.It was 3.30p.m.and his par...
【单选题】First you board the train. Then you explain the situation to the ______________ and get a ticket.
A.
cashier
B.
counter
C.
attendant
D.
chef
【简答题】Is the world really going mad? 1._____day I was sittng in a restaurant 2._____ a quick drink and a talk with a few friends when it suddenly 3._____ me that almost everyone in the restaurant was smokin...
【单选题】听力原文： The Office of Motor Vehicles, providing services related to driver's licenses, motor vehicle registration, and motor vehicle inspection, is located at 124 State Street, right next to City Hall a...
A.
Every day of the week.
B.
Only on Monday.
C.
Only on Friday.
D.
Monday through Friday.
【简答题】You board an inflatable liferaft that has been hand launched from a sinking vessel. What should you do FIRST after everyone is onboard the liferaft?A. Cut the painter.B. Operate the radio equipment.C...
【单选题】You board the train first and then ___________. 您先上车然后 补一张票 。
A.
make up a ticket
B.
buy a new ticket
C.
buy one more ticket
D.
buy a replacement ticket
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