For those who must be cautious about their health, this is a warning flag.
She already thought the warning flags were up, which irritated him.
"It should have been enough to raise a warning flag before the election."
The warning flags were up early in this game.
That came with major warning flags: not a good idea.
Such selling is sometimes seen as a warning flag about a company's prospects.
This time the eyebrow went up like a warning flag.
We raised the warning flag to the entire executive board.
His ghost is said to be wave a red warning flag in the area.
"We couldn't sustain the level of the past few months, so last month's figures are a yellow warning flag."
