这个错误probaby与我的路径/环境变量有关，但我不太了解解决这个问题的那些，任何帮助都表示赞赏。
git pull
git: 'pull' is not a git command. See 'git --help'.
Did you mean one of these?
apple
shell
git --exec-path
/opt/local/libexec/git-core
which git
/usr/bin/git
echo $PATH
/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/local/MacGPG2/bin`