it is uncertain whether造句

1、It is uncertain whether we'll attend the meeting or not.
我们是否参加那个会议还没有确定。

2、However, it is uncertain whether or not the breed existed in the area even earlier.
不过，这是未知数或不存在的品种在该地区，甚至更早。

3、It is uncertain whether he can come to Jenny's birthday party or not.
他是否能够参加詹妮的生日聚会还不确定。