请英语高手指教下面这句英语中sickjoke的谓语是什么?Hencethesickjokethatthereasonwehave...请英语高手指教下面这句英语中sickjoke的谓语是什么?Hencethesickjokethatthereasonwehavenotbeencontacted

Question

请英语高手指教下面这句英语中sick joke 的谓语是什么?Hence the sick joke that the reason we have...
请英语高手指教下面这句英语中sick joke 的谓语是什么?Hence the sick joke that the reason we have not been contacted by an alien civilizatian is that civilizations tend to destroy themselves when they reach our stage.

Answer 1

没有谓语啊,这句话只是在解释“由此得出这样一个sick joke”,什么样的joke呢,后面即做出解释：我们还没有与外来文明取得联系的reason 是当他们抵达我们的地盘时,文明会先将他们毁灭.
is是the reason的谓语.