在根目录下的etc目录内有两个目录，有dir2父目录和其内的子目录subdir2在根目录下的home目录内有子目录，home目录内有子目录dirr使用哪条命令切换到子目录subdir2位置[root@RHEL7-1 etc]# ()使用哪条命令切换到子目录dirr位置[root@RHEL7-1 etc]# ()
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The subject of an email should be____________.
A. short and to the point
B. straightforward and accurate
C. vague
D. long
When greeting someone whose name you don’t know you can use:
A. Hi,
B. Hello,
C. To whom it may concern
Dear Sir/Madam
When writing a business email, try to avoid:
A. slangs and unnecessary contractions
B. emoticons and emojis
C. profanity
D. jokes
A complimentary close is used for ____________.
A. saying goodbye
B. sending your love
C. asking people to write back
D. none of the above
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