单项选择题

After Benjamin Franklin's discovery, others showed that _______.

A．the tops of thunderclouds have a great positive charge
B．the bottoms of the clouds have a great negative charge
C．only the middles of thunders are electrically charged
D．both A and B

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单项选择题

For many people, overeating and overspending are as _______ to Christmas as candles and holly.

A．integral
B．suitable
C．inevitable
D．compatible

单项选择题

My husband likes early American furniture, but I prefer _______ styles, designs that reflect today’s times.

A．noble
B．neutral
C．contemporary
D．simple