only 修饰 few 或 little 时,通常要与 a 连用.
Only a few children have read this book.
只有几个孩子看过这本书.
所以only a few就是few
再看看其他用法
few修饰可数名词复数.
2．few (= not many; hardly any)含否定意义；a few (= some; several; a small
number of) 含肯定意义.
3． not a few = no few = quite a few = a good few = many.
4． 当 few受 every,last,past,next,some,very等词所修饰时,表示肯定意义,few之前不再有冠词.如：
In the last few minutes,he checked up his paper again.
It took us some few days to repair the machine.
They are very few in number.
There were too few of them.
He goes to see his grandma every few weeks.
