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Foods and fluids are mixed in the stomach by its muscular contractions.通過胃部肌肉的收縮食物和流質(zhì)在胃中混合。Contractions are much more common in speech than in writing.縮略詞在口語里比在書寫中常見得多.Muscle contractions are powered by the chemical aden...

n.收縮( contraction的名詞復(fù)數(shù) )，縮減，縮略詞，（分娩時(shí)）子宮收縮...

contractions的音標(biāo)：...