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【多选题】
事实证明，发生瓦斯事故的煤矿，大多都存在通风系统不合理、不可靠问题，具体表现在：（）等造成工作面无风、微风、循环风作业，导致瓦斯局部聚集，发生瓦斯事故。特别强调的是，在矿井通风大系统合理可靠的前提下，局部通风十分关键。A.
如采区没有实现分区通风
B.
采、掘工作面通风不独立、风量不足
C.
存在不合理串联通风、角联通风，高突矿井没有专用回风巷道
D.
通风设施不可靠造成漏风，局部通风机管理不善和风筒漏风
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举一反三
【单选题】Most emerging adults are very ______, believing that they have good chances of living "better than their parents did."
A.
optimistic
B.
pessimistic
C.
independent
D.
dependent
【单选题】According to the passage, which of the following is not the cause of mental health problems of emerging adults?
A.
They are not restrained by the obligations as real adults.
B.
Some of them are minors of the society.
C.
They are more affluent than their predecessors.
D.
They may have jail experience when they were adolescents.
【单选题】Most emerging adults are very _________, believing that they have good chances of living "better than their parents did."
A.
extreme
B.
occasional
C.
optimistic
D.
pessimistic
【简答题】Most emerging s are very ( ) , believing that they have good chances of living "better than their parents did."
【单选题】在用键盘切换输入法时,用 ( )可以在中、英文输入法之间切换;用( )可以在安装的全部输入法之间切换。
A.
Ctrl + 空格、Ctrl + Shift
B.
Ctrl + Shift、Ctrl + 空格
C.
Ctrl + Shift、Ctrl + 回车
D.
Ctrl + 回车、Shift + 回车
【单选题】在用键盘切换输入法时,用 () 可以在中、英文输入法之间切换;用 () 可以在安装的全部输入法之间切换.
A.
+ 、 +
B.
+ 、 +
C.
+ 、 +
D.
+ 、 +
【单选题】在用键盘切换输入法时,用 () 可以在中、英文输入法之间切换;用 () 可以在安装的全部输入法之间切换.
A.
+ : +
B.
+ : +
C.
+ : +
D.
+ : +
【单选题】Most emerging adults are very _____, believing that they have good chances of living "better than their paretns did."
A.
pessimistic
B.
grateful
C.
optimistic
D.
depressed
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