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Words and Their StoriesLearning Expressions with VOA
Processed with VS1Use “red flag” to describe a warning sign without turning suspicion into proof.
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Source: VOA Learning English · Words and Their Stories
View original article & transcriptA red flag is a sign that something may cause trouble or danger. It can be raised by a person who expresses concern, and it is a reason to pay attention—not proof by itself.
Cultural note: Calling a person a “red flag” can oversimplify them or spread an accusation. Describe the specific behavior and distinguish a concern from a confirmed fact.
Keep exploringA warning sign deserves attention, but it does not tell the whole story. Learn the phrases that mark concern while leaving room for evidence.
Phrase guide · 5 expressions
Original explanations and examples, created for learners. Save a card for later or hear the phrase spoken by your browser.
Describe a possible sign of trouble.
Meaning
A warning sign that something may be wrong or risky.
Tone & use
Often used for a concern that deserves investigation. A red flag is not conclusive proof.
Example
“The unusually vague contract was a red flag, so we asked a lawyer to review it.”
Meaning
A statement or sign that alerts someone to possible danger or trouble.
Tone & use
More direct than “red flag.” A warning may be official, explicit, or based on observed facts.
Example
“The weather service issued a warning before the storm reached the coast.”
Explain how a concern is brought to other people’s attention.
Meaning
Draw attention to a possible problem or danger.
Tone & use
Use when someone voices concern. In work settings, state the concrete evidence as well as the concern.
Example
“The missing safety report raised a red flag for the inspection team.”
Meaning
Cause several concerns or warning signs to become noticeable.
Tone & use
Often used when multiple details create concern; it still does not establish that wrongdoing occurred.
Example
“Repeated unexplained delays raised red flags, so the board requested an update.”
Separate warning language from certainty.
Meaning
An indication that a situation may not go well.
Tone & use
A broad, everyday alternative to “red flag”; it can refer to a minor or serious concern.
Example
“A second power outage was a bad sign for the outdoor event.”
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