Flags wave high.

Meaning: This means the flags on the sandcastle are high up and moving in the wind.

Choice of Words: Flags are pieces of fabric that are used as symbols or for signaling. Wave means to move back and forth in a regular motion. High means to a great extent or distance. When you put them together, "Flags wave high" describes the flags on a sandcastle as being high up and moving in the wind.

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Related Expressions