将当前目录中的 myfile.txt 文件压缩成 myfile.txt.tar.gz 的命令为（)
A. tar -cvf myfile.txt myfile.txt.tar.gz
B. tar -zcvf myfile.txt myfile.txt.tar.gz
C. tar -zcvf myfile.txt.tar.gz myfile.txt
D. tar -cvf myfile.txt.tar.gz myfile.txt
查看答案
在建立一个 tar 归档文件的时候，可列出详细列表的命令是（）
A. tar -t
B. tar -cv
C. tar -cvf
D. tar -r
Mary _____ in Wuhan since 2004.
A. lives
B. lived
C. have lived
D. has lived
-Where is Cathy?-She _______ Beijing, and she will be back in three days.
A. has been to
B. has been in
C. has gone to
D. went to
-Would you like to go to the East Lake with me, Joy?-No, I________ that place a thousand times.
A. have gone to
B. have been to
C. have went to
D. have been in
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