a set of keys ,a set of ...意为“一串···”,那么两串钥匙怎么表示______________________.

题目

a set of keys ,a set of ...意为“一串···”,那么两串钥匙怎么表示______________________.
Is this his brother 变为复数形式 _____________________________
I am a boy 变为复数形式 ________________________________
That is an orange 变为复数形式 ________________________________
单数句变为复数句时要注意的几个问题.
I 变为 _____
you 不变,因为________
she/he/it 变为_______
单数名词变为_________
英文的书信格式与中文相同吗?你来简单总结下吧.
答:________________________________________________________________________________________________.

答案

答案依次为：
two sets of keys
Are these his brothers?
We are boys
These are oranges
we,有你或你们两个意思,they,单数名词的复数形式
不相同