The starfish clung to the rock like a magnet.
Meaning: This sentence describes the starfish holding on tightly to the rock.
Choice of Words: Clung means to hold on tightly to something. Rock is a hard, solid substance that is found in the Earth. Magnet is an object that attracts metal. When you put them together, "The starfish clung to the rock like a magnet" means that the starfish was holding on tightly to the rock, like a magnet holds on to metal.
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Related Expressions