I didn't know -----they would have a meeting here the next week

I didn't know -----they would have a meeting here the next week
I didn't know -----they would have a meeting here the next week

I didn't know -----they would have a meeting here the next week
how or whehter

whether

if or whether or why
我不知道他们是否会在下星期来这里开会
因为时间＼地点都有了
只能是判断或者疑问

whether or if

whether or if