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【单选题】
关于多普勒效应,下述说法正确的是A.
只要波源在运动，就一定能观察到多普勒效应 。
B.
当波源静止，观察者运动时，观察不到多普勒效应 。
C.
只要声源在运动，观察者总是感到声音的频率变高 。
D.
当声源相对于观察者运动时，观察者听到的声音频率可能变高， 也可能变低
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【简答题】An infant can recognize a lot of sounds by the time he or she is a year old.
【单选题】According to the study, an infant child can form. friendship as young as______.
A.
six months old.
B.
one year old.
C.
eighteen months old.
D.
two years old.
【单选题】He told me that the couple had died and he was __19_ by their children to find me.
A.
encouraged
B.
fond of
C.
employed
D.
forced
【单选题】A father brings his 3-month-old infant to the clinic, reporting that the infant has a cold, is having trouble breathing, and “just doesn’t seem to be acting right.” Which of the following actions woul...
A.
Check the infant’s heart rate.
B.
Weigh the infant.
C.
Assess the infant’s oxygen saturation.
D.
Obtain more information from the father.
【单选题】He told me that the music was ______ worth _______ again.
A.
well, to listen to
B.
very, listening to
C.
very, to listen to
D.
well, listening to
【简答题】He told me that the factory [填空(1)] (close) down.
【简答题】简述合作作品的构成要件及著作权归属。
【简答题】He told me that the book was not ______ (worth) of reading.
【多选题】The nurse is collecting data on a 3-month-old infant, which of the following behaviors are not correct?
A.
Holding the bottle during feeding
B.
Crying when a strange comes near.
C.
Creeping on her hands and knees.
D.
Smiling in response to the mother’s voice.
E.
Waving bye-bye
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