Questions about example sentences with, and the definition and usage of "Surveillance"

A: It means somebody is or may be watching you through a video camera.
The sign you posted suggests they are looking for people who may be spitting in a public place, and maybe there is a fine for doing that.

A: Keep track of what's happening.

A: close observation, especially of a suspected spy or criminal.

"he found himself put under surveillance by British military intelligence"

A: ‏مرابقة

A: This area has many thieves. Therefore, we need to install surveillance cameras to our house.

A surveillance team is needed in the airport.

People in the store will be under surveillance.

A: As in watching someone closely: “The CIA has him under surveillance.”

As in watching a place to prevent crime or gather evidence on a criminal: “The store is under video surveillance.” or “They put a covert surveillance team in place to watch the smugglers.”

As in security cameras or videos: “The surveillance cameras watched the gas station from above.” or “The police watched the surveillance video to catch the thief.”

A: The surveillance cameras are always watching.
The Surveillance video showed the shop being robbed.
The suspects were under police surveillance.

A: @carstrk They mean the same thing.

A: Surveillance is neutral, scruteny is more insistent.

A: I didn't think that only those subject to surveillance would be monitored.

A: Surveillance Camera.

A: Check the question to view the answer

A: Check the question to view the answer

A: I think it's more natural to say
"He was no doubt making plans to take down the ruler during that time."

A: *I use it as a baby monitor.

A: Natural but formal

A: In casual / informal speech this sentence is acceptable.

However, in more formal speech or written English, it is not acceptable. Instead you should say either:

"I have surveillance photos that say otherwise."
OR
"I've got surveillance photos that say otherwise."

A: Perfect