to spy on

USAGE SUMMARY

The phrase "to spy on" is correct and usable in written English.
It can be used when referring to the act of secretly observing or monitoring someone or something, often without their knowledge. Example: "He was accused of trying to spy on his neighbors through their windows."

✓ Grammatically correct

News & Media

Academia

Human-verified examples from authoritative sources

Exact Expressions

60 human-written examples

Moreover, it is not our job to spy on customers".

The New York Times

They said they never did so to spy on students.

The New York Times

Or one can use it to spy on one's children (recommended).

The New Yorker

To spy on their owners?

The New Yorker

Someone still wants to spy on us!

The New York Times

Is it right to spy on Muslims?

The Guardian - Opinion

Everybody's trying to spy on everybody else".

The Guardian - Books

It wasn't to spy on them.

The Guardian

They actually wanted to spy on the entire United States.

Massachusetts Institute of Technology

metadata is valuable to the NSA to spy on you.

Stanford University

(His reason: "roommate used webcam to spy on me").

The New Yorker

Expert writing Tips

Best practice

When writing about espionage or security matters, use "to spy on" for clarity and impact. The phrase directly conveys the idea of secret observation, making it suitable for news reports, academic papers, and fictional narratives.

Common error

Avoid substituting "to spy on" with overly formal alternatives like "to conduct surveillance of" in casual contexts. Overly formal terms can sound unnatural or pretentious in everyday conversations or informal writing.

Linguistic Context

The phrase "to spy on" functions as an infinitive phrase, typically acting as a verb phrase that describes the action of secretly observing someone or something. Ludwig AI indicates that this phrase is correct and usable in written English.

Expression frequency: Very common

Frequent in

News & Media

58%

Academia

21%

Science

21%

Less common in

Formal & Business

0%

Encyclopedias

0%

Wiki

0%

Ludwig's WRAP-UP

The phrase "to spy on" is a versatile infinitive phrase used to describe the act of secretly observing someone or something. Ludwig AI confirms its grammatical correctness and widespread usage, with examples spanning news articles, academic papers, and general discourse. Its neutral register makes it suitable for various contexts, though synonyms might be preferred for highly formal or informal settings. The phrase's frequency is high, indicating its common integration into the English lexicon, with the main contexts being in "News & Media", "Academia" and "Science".

More alternative expressions

Phrases that express similar concepts, ordered by semantic similarity:

to secretly observe

Focuses on the act of watching without being noticed.

to watch stealthily

Implies a cautious and secretive manner of watching.

to keep under surveillance

Emphasizes continuous and systematic observation, often by authorities.

to conduct surveillance of

Formal term for systematically observing someone.

to monitor covertly

Highlights the secret nature of the monitoring activity.

to keep tabs on

Suggests monitoring someone's activities or whereabouts.

to eavesdrop on

Specifically refers to secretly listening to conversations.

to tail

Implies following someone discreetly, often on foot.

to shadow

Similar to tailing, suggesting close and discreet following.

to pry into

Conveys an intrusive and unwelcome investigation.

FAQs

How can I use "to spy on" in a sentence?

You can use "to spy on" to describe the act of secretly watching someone. For instance, "The government was accused of trying "to spy on" its citizens".

What's a less direct way of saying "to spy on"?

Alternatives include phrases like "to observe secretly" or "to monitor covertly", which convey the same idea with varying degrees of formality.

Is "to spy on" formal or informal?

"To spy on" is generally considered neutral and can be used in both formal and informal contexts, depending on the surrounding language. However, in highly formal writing, you might consider more precise alternatives.

Which is correct, "spy on" or "spy upon"?

"Spy on" is the more common and accepted form. "Spy upon" is archaic and rarely used in modern English. Stick to "spy on" for clarity and contemporary usage.