I don't know if she's got a boyfriend or not.是什么意思？

I don't know if she's got a boyfriend or not.

我不知道她有没有男朋友。

know

v. 知道，了解，认识，确信；n. 知情；

例句
I know you're above me socially, but I must say I find your attitude offensive...
我明白你的社会地位比我高，但我得说我觉得你的态度很粗鲁。

if

conj. 如果，倘若，即使，〈口〉是否，假设；n. 条件，设想；

例句
She was old enough to absent herself from the lunch table if she chose...
她长大了，可以自己做主不来吃午餐了。

got

v. 得到(get的过去式和过去分词)，抓住，说服，受到（惩罚等）；

例句
They said goodbye to him as he got aboard the train at Union Station.
当他在联合火车站登上火车之际，他们向他道别。

boyfriend

n. 男朋友，情郎；

例句
It's a bit much expecting me to dump your boyfriend for you.
指望我替你甩掉你的男朋友，有点儿过分了吧？

or

conj. 或，或者，还是，不然，否则，左右；prep. <古、诗>在…之前，比…更早；n. [纹章]黑金色、黑色；

例句
We are scared to abandon ourselves to our feelings in case we seem weak or out of control.
我们不敢放纵自己的情感，以免显得太过软弱或缺乏自制。

not

adv. 不，[用以表示否定、否认、拒绝、禁止等]不是，几乎不，未必，没有[用于否定后面的词或短语]；

例句
It became very clear that the incident was not just an aberration, it was not just a single incident.
事实已经很清楚，这件事不是偶发的，它并不是一起孤立的事件。