For example, suppose you use a semicolon to combine two commandsin which the proper execution of the second command depends entirely upon the successful completion of the first.
例如，假设您使用分号来组合两个命令，其中第二个命令的正确执行完全依赖于第一个命令的成功完成。
2
We separate commands using a semi-colon (;) and use the same global substitution that we used in the second script to replace 'a' with 'a'.
我们使用分号(；)分隔命令，并使用第二个脚本中用到的全局替换来将‘a’替换为‘a’。
3
The second quirk is that you cannot pass arbitrary shell commandsin.