whenever       
 adverb, conjunction uk/wenˈev.ər/ us/wenˈev.ɚ/
B1 每当,无论何时
every or any time
  I blush whenever I think about it. 每当我想到这个就会脸红。 
 Whenever I go there they seem to be asleep. 每次我去那儿他们似乎都在睡觉。 
 I try to use olive oil whenever possible. 我尽可能使用橄榄油。 
 "Will it be okay if I do it tomorrow?" "Sure, whenever (= then or at any other time)." “我明天做行不行?”“当然可以,什么时候都行。” 
 Do it in a spare moment at the weekend or whenever - it really doesn't matter. 在周末或其他别的什么空闲时间做都行——真的没关系。 
 I'm talking about last July or whenever it was you got back from India. 我正在谈论你从印度回来的时间,去年七月还是其他什么时候。 
 - More examples
 - There's a night safe outside the bank, so you can deposit money whenever you wish.
 - It's funny how Alec always disappears whenever there's work to be done.
 - Just because I'm lending you my dress for tonight doesn't mean you can borrow it whenever you want to.
 - He goes to the opera whenever he can.
 - Come and see us whenever you're in town - you're always welcome.
 
whenever       
adverb uk/wenˈev.ər/ us/wenˈev.ɚ/
 究竟什么时候,到底什么时候(用于代替 when 以加强语气,表示惊讶)
used instead of "when" to add emphasis to a phrase, usually expressing surprise
  Whenever do you get the time to do these things? 你到底什么时候有时间做这些事情? 
 Whenever did Jane see a fortune teller? 简究竟什么时候找过算命先生?