单项选择题

Since 1939, numerous scientific studies ______.

A．proved smoking causes fatal diseases
B．proved smoking causes life-shorting diseases
C．proved smoking is a health risk
D．had been made to prove whether smoking causes life shorting

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热门试题

单项选择题

Cigar and pipe smokers consume ______.

A．slightly less nicotine than cigarette smokers
B．less nicotine than cigarette smokers
C．no less nicotine than cigarette smokers
D．much less nicotine than cigarette smokers

单项选择题

According to the author, ______.

A．the use of clich6s can make a person’s speech very dull
B．a clich6 is used to describe things that are too beautiful for words
C．the phrase "as hard as nails" is no longer in use
D．cliches are .something you can only learn from Shakespearean play