单项选择题

A．Plants can produce some poisonous chemical for defence against insects.
B．Insects have been eating plants for many million years.
C．Insects have developed ways of dealing with poisonous chemicals produced by plants themselves.
D．Insects have already developed some resistance to man-made poisons.
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单项选择题
A．On the cliffs of an island.B．In the eaves of an island.C．Under the holy picture of the Virgin.D．In the Virgin convent of an island.
A．On the cliffs of an island.
B．In the eaves of an island.
C．Under the holy picture of the Virgin.
D．In the Virgin convent of an island.
单项选择题
A．The apartment is too far from the campus.B．The apartment needs a lot of repair work.C．She’s having trouble with the owner of the apartment.D．Her roommate won’t share expenses.
A．The apartment is too far from the campus.
B．The apartment needs a lot of repair work.
C．She’s having trouble with the owner of the apartment.
D．Her roommate won’t share expenses.
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