蚊子是传播疾病的致命杀手。

Mosquitoes are dangerous ___killers that spread diseases.

这次数学考试真是要命，题目太难了。

That math test was a ___killer — the problems were so difficult.

这周的健身课简直是个杀手，我到现在都浑身酸痛。

This week's workout class was a real ___killer — I'm still sore all over.

她讲的那个笑话真是绝了，所有人都笑得停不下来。

Her joke was such a ___killer that everyone couldn't stop laughing.