vi设置了expandtab时，如何插入制表符？
请教各位大虾了，多谢！ vi linux
[解决办法]
:help et

'expandtab' 'et' boolean (default off)
local to buffer
{not in Vi}
In Insert mode: Use the appropriate number of spaces to insert a
<Tab>. Spaces are used in indents with the '>' and '<' commands and
when 'autoindent' is on. To insert a real tab when 'expandtab' is
on, use CTRL-V<Tab>. See also :retab and ins-expandtab.
NOTE: This option is reset when 'compatible' is set.