不是固定搭配，例如：
1、A large number of people have applied for the job.許多人申請了這工作。
2、Water covers a large proportion of the earth's surface.水覆蓋了地球表面的大部分。
3、There were a large number of candidates for the job.有許多求職者申請這份工作。
4、Somewhere along the line a large amount of money went missing.有一筆鉅款在某一環節上不翼而飛。
不是。
large是形容詞，後面須有名詞。如a large amount of， a large quantity of等。
後面修飾可數名詞的有 large numbers of等，後面修飾不可數名詞的有 a large/great amount of ，large /great amounts of等。
例句：
A large percentage of population live in big cities. 很大比例的人口住在城市。
