According to Paragraph 3, which of the following is NOT true about yawning？
A. It always happens in groups
B. It makes people relax under pressure
C. It is caused by changes in brain chemistry
D. It usually lasts approximately six seconds
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The passage mainly discusses______.
A. the rates of yawning
B. the misconceptions of yawning
C. the secrets of yawning
D. the applications of yawning
Hallowell argues in his new book, Driven to Distraction at Work: How to Focus and Be More
The word "contagion"(Para. 4)most probably means______.
A. spreading
B. learning
C. protection
D. imitation
Selfie sticks have been baned in case of all the following problems EXCEPT______.
A. invasion of personal space
B. damage to the artwork
C. waste of printed guidelines
D. danger to camera users
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