名词性从句
连词
that/if/whether/because等
连接代词
what/which/who/whom/whose等
定语从句
关系代词
who/whom/which/that/whose/as
状语从句
时间
when/while/as/before/after/since/the moment/til等
条件
if/unless/as long as/in case/given that/provided that
目的
so tht/in order that/in case
比较
as...as/than/the+比较级,the +比较级
让步
Although/though/as/while/even if/though
