summer holiday与summer

两者没有区别

但summer

holiday与summer

holidays

做主语时

要注意谓语动词前者用单数，后者用复数，例句如下：

Seven

weeks'

summer

holiday

every

year

is

written

into

our

school

calender.

每年7周暑假写进了我们的校历。

Summer

holidays

normally

start

at

the

end

of

July.

暑假一般放在7月底开始。