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【单选题】
网络层、数据链路层和物理层互连设备转发或传输的数据单元分别为.A.
报文、帧、比特
B.
包、报文、比特
C.
包、帧、比特
D.
数据块、分组、比特
拍照语音搜题，微信中搜索"皮皮学"使用
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皮皮学刷刷变学霸
举一反三
【单选题】(Only then)(he became) aware of (the fact) that there were more difficulties ahead (than) he had expected.
A.
Only then
B.
he became
C.
the fact
D.
than
【单选题】(Only then) he (became) aware of (the fact) that there were more difficulties ahead (than) he had expected.
A.
Only then
B.
became
C.
the fact
D.
than
【简答题】He only then became aware (意识到) of the ers of the jungle. (Only then...)
【单选题】Prof Flynn found no students in the lecture hall when he arrived. Only then did he realize that he came ______ early.
A.
too much
B.
much too
C.
so much
D.
much so
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