smell a rat
US /smɛl ə ræt/
UK /smɛl ə ræt/

1.
觉得不对劲, 察觉到阴谋
to suspect that something is wrong or that someone is trying to trick you
:
•
When he offered to pay for everything, I started to smell a rat.
当他提出要支付所有费用时,我开始觉得不对劲。
•
The police smelled a rat when the suspect's story kept changing.
当嫌疑人的故事不断变化时,警方觉得不对劲。