【单选题】在听说游戏活动创设游戏情境之后,教师告诉幼儿游戏的基本规则、步骤和要求可通过( )
【单选题】自动增益控制电路在输入信号较弱时,使接收机的增益( ),在输入信号较强时,使接收机的增益( )。
【简答题】The edge of the wise over the unwise lies in their tendency to __________ about the purpose of their life.
【单选题】要存储一个long型的值,需要( )字节的存储空间。
【判断题】α,β-不饱和醛中,由于羰基氧的吸电子作用在共轭体系内传递,使β-碳也带部分正电荷,因此,亲核试剂既可进攻羰基碳,发生1,2-加成,也可进攻 β-碳,发生1,4-加成。
【单选题】About the tendency of food in America, which of the following ones is NOT true?
【单选题】When did the conversation take place?
A.
At about five o'clock.
B.
At about nine o'clock.
D.
At about eleven o'clock.