【单选题】睡眠以______为主宰。神静则寐,神动则寤;心安志舒则易寐,情志过极则难寐。(单选2 分)
【判断题】声音是由物体振动引起的,物体振动消失后,声音会消失。
【简答题】如图所示,在演示声音是由物体振动引起的实验中,将正在发声的音叉紧靠悬线下的轻质小球,小球被多次弹开。在此实验中小球的作用是把音叉的微小振动放大,便于观察。这个实验用到的研究物理问题的方法是 。
【单选题】The author suggests that the variety of incidents in the Odyssey is likely to deter the reader from ______.
A.
concentrating on the poem' s mythological features
B.
concentrating on the psychological states of the poem' s central character
C.
accepting the explanations that have been offered for the poem' s popularity
D.
accepting the poem' s scheme of divine justice
【单选题】如图所示,在演示声音是由物体振动引起的实验中,将正在发声的音叉接触水面,水花四溅.在此实验中水的作用是( )
【判断题】声音是由物体振动引起的,物体振动消失后,声音也会消失。
【判断题】Levinson suggests replacing all the maxims, except for the maxim of quality, with two principles: The Quantity Principle and The Relation Principle.