The jury is out on whether or not this is true

　　這是否屬實(shí)仍未得出定論。

　　He was faced with the dilemma of whether or not to return to his country

　　要不要回國，他進(jìn)退兩難。

　　You examine a patient and then you decide whether or not to operate.

　　先為病人作檢查，然后再?zèng)Q定是否做手術(shù)。