spy

英 /spaɪ/ 　美 /spaɪ/

n. 间谍；密探Someone who secretly gathers information about a country or organisation
v. 从事间谍活动；暗中监视To secretly watch someone or gather information about them
v. 突然发现；瞥见To notice someone or something, especially after looking carefully

I spied a tiny kitten hiding behind the flowerpot.

我瞥见一只小猫躲在花盆后面。

Many users worry that connected devices could spy on their activities without permission.

许多用户担心联网设备可能未经允许就暗中监视他们的活动。

搭配

spy on someone 暗中监视某人spy novel 间谍小说spy network 间谍网

监视某人用spy on；过去式和过去分词为spied。

spying (n.)