【我不知道的小知识点】1.命令执行问题

qimuzhi

ligf@hot ~/tmp/shell/run-commands $ cat f.sh
#!/bin/bash -
#===============================================================================
#
#          FILE: f.sh
#
#         USAGE: ./f.sh
#
#   DESCRIPTION:
#
#       OPTIONS: ---
#  REQUIREMENTS: ---
#          BUGS: ---
#         NOTES: ---
#        AUTHOR: YOUR NAME (),
#  ORGANIZATION:
#       CREATED: 2015年09月30日 09:34
#      REVISION:  ---
#===============================================================================

CMD="ls && ls aaa && ls aasdf"
$CMD

ligf@hot ~/tmp/shell/run-commands $ ./f.sh
ls: cannot access &&: No such file or directory
ls: cannot access ls: No such file or directory
ls: cannot access aaa: No such file or directory
ls: cannot access &&: No such file or directory
ls: cannot access ls: No such file or directory
ls: cannot access aasdf: No such file or directory
ligf@hot ~/tmp/shell/run-commands $ ls && ls aaa && ls aasdf
f.sh
ls: cannot access aaa: No such file or directory
ligf@hot ~/tmp/shell/run-commands $
-------------------
上面的shell相信大家都看明白了吧？
这是为什么？script要如何才能实现和在terminal 直接敲命令的效果？ 反之要如何？

songyc_2015

eval $CMD，要这样么？