请问 of which 是什么从句 为什么用wich 为什么加OF
问题描述：
请问 of which 是什么从句 为什么用wich 为什么加OF
When anyone opens a current account at a bank,he is lending the bank money,repayment of which he may demand at any time,either in cash or by drawing a cheque in favour of another person.
答
是定语从句.需要详细分析：
which是连接代词,指前面提到的money,repayment of which又在从句中做谓语demand 的宾语.需要加of的原因是,which相当于the money,修饰repayment,做repayment的后置定语,所以要用of连接.