1、It is uncertain whether we'll attend the meeting or not.
我們是否參加那個會議還沒有確定。

2、However, it is uncertain whether or not the breed existed in the area even earlier.
不過，這是未知數(shù)或不存在的品種在該地區(qū)，甚至更早。

3、It is uncertain whether he can come to Jenny's birthday party or not.
他是否能夠參加詹妮的生日聚會還不確定。

it is uncertain whether翻譯