问题描述：
高中英语The telephone line to the headmaster is always busy.
--------The telephone line to the headmaster is always busy.
--------Someone______the telephone.
A must use Bmust be using
为什么选B不选A?always不是总是的意思吗,应该用一般现在而不是现在进行啊?
--------The telephone line to the headmaster is always busy.
--------Someone______the telephone.
A must use Bmust be using
为什么选B不选A?always不是总是的意思吗,应该用一般现在而不是现在进行啊?
问题解答：
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