when+doing 还是when+to do sth.
when sb.do sth.还是 when sb.doing sth.
when doing sth 还是 when do sth (语法问题)
when are you doing sth?正确还是when are you do sth?正确?
什么时候when sb do sth 可变成when doing sth
when的结构,不是时间状语从句,不是现在完成时,是when sb do sth,还是when sb doing sth
when i do还是when i doing
expect to do sth还是doing sth?
mind doing sth还是 to do sth
learn+to do sth 还是 doing sth
finish to do sth还是doing sth
promise doing sth还是to do sth
plan+to do sth.还是doing sth.还是 do sth.