Hi, all!

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Miss Champagne was dressed in an extraordinary mermaid outfit. It was
green and silver with velvety sea flowers dangling from it. It had small
teardrop shapes of net all over it, a halter neck, a very low front, and
a circular gap at stomach level revealing Suky's emerald studded belly
button.
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Is there a rule, or consideration why we omit an article or pronoun before
"stomach level"?

Bye, all!
Alexander Koryagin

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