Rats can't vomit or burp because of a limiting wall between their two stomachs and their inability to control the diaphragm muscles needed for the action.

老鼠不能反胃或打嗝，因为它们受到了两个胃之间隔离墙的限制，它们也不能有效调节横隔膜肌肉的活动。

youdao

And turns out it's two muscles working together.

他发现这关乎两组肌肉的共同运用。

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He is almost totally paralyzed, speechless and wheelchair-bound, able to move only his facial muscles and two fingers on his left hand.

他几乎完全瘫痪，不能说话，离不开轮椅，能够活动的只有他面部的肌肉和他左手的两个指头。

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Seeking to flex their parliamentary muscles, Golkar and Miss Megawati's Indonesian Democratic Party of Struggle, the two largest parties in the Nationhood Coalition, have discovered they are not as strong as they had hoped.

ECONOMIST: At last, a real opposition

By using two air muscles to pull a joint in different directions, the robot hand is capable of strong and precise actions.

ECONOMIST: Mechanical hand seeks dangerous, dirty and dull jobs

Two weeks ago, I awoke at 6:30 a.m. with a tingly face and sore abdominal muscles.

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