rapid,fast,soon,quickly的区别

rapid,fast,soon,quickly的区别
I asked my mum to take me to travel to Hong Kong,___,she agreed
A.believing it or not B.that is to say
C.believe it or not D.to believe it or not
(希望有解释）
India has a ___ number of population than China.
A.smaller B.less C.fewer D.shorter
--When will the manager take his holiday?
--He ___leave until Saturday.
A.is expected to B.expects to
C.is not expected to D.does not expect(希望有解释）
until用法
When we are in England,China is a__ country.
A.east B.easter C.eastward D.eastern
上述四个词的区别
as和when的区别
form的用法
当表示一些,一些,一些时,用some,some,other还是some,other,other