在R7初值为00H的 情况下,DJNZ R7,rel指令将循环执行____次。(5.0)
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欲使P1口的低4位输出0, 高4位不变, 应执行一条____指令。(4.0)
One of our customers is in the market __________Chinese white tea.
A. of
B. for
C. on
D. in
We would ______ very much if you send us some samples immediately.
A. appreciate
B. appreciate it
C. appreciated
D. appreciate you
Our company has 20 years' experiece _____ the machinery line.
A. on
B. in
C. about
D. of
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