The new dictionaries are very useful. They well and already. A. sell; have been sold out

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(答案→)A. sell; have been sold out
B. sold; had sold out
C. sell; sell out
D. are sold; have been sold out
解析：考查时态语态，第一空是sell，主动表被动，表示这些字典的特点：卖得好，时间是already，第二空考查现在完成时的被动，句意：新的字典非常有用，他们很好卖并已经被卖光了。选A。