whether
01
是否
used to talk about a doubt or choice when facing two options
例子
He's trying to figure out whether he should study abroad or stay in his home country.
他正在试图弄清楚是否应该出国留学还是留在自己的国家。
02
是否, 如果
used to show an inquiry; if
03
是否, 不管
in any case
