It still puzzles the science world why some mammals produce their young ______ a

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It still puzzles the science world why some mammals produce their young ______ and hatching while
others _____ to young babies. [ ]

A. lying eggs; giving birth
B. by laying eggs; by giving birth
C. by laying eggs; give birth
D. laying eggs; giving birth

答案

举一反三

The parents have devoted themselves to bringing up their children and now it is time for the children, ______, to show their devotion to their parents. [ ]

A. in their turn
B. in their return
C. in return
D. in their turns

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It is never harmful _____ you to be polite and gentle to others and ______, as is often the case, you can get what you want. [ ]

A. to; thus
B. for; thus
C. of; therefore
D. with; however

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The author of the novel designed the plots of the story so badly that some of the plots are often ______ each other. [ ]

A. contrary with
B. to the contrary
C. contrary to
D. on the contrary to

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Totally ______ accident, the businessman picked up a _______ antique(古董) in the
flea market(跳蚤市场).[ ]

A by; true
B. in; indeed
C. with; actual
D. by; genuine

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Nobody could have ever imagined that the poor man ______ _______ be a  millionaire.    [     ]
A. in rag; could
B. in rags; should be
C. wearing poorly ; should
D. dressed poorly; might

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