And I rolled up the window and before you know it " he had punched out the window."
我讲车窗门拉起,没等我反应过来,他一拳就砸在了玻璃上“
This tube, this hollow tube, which food passes through is made up of many, many epithelial cells which directly abut one another and would be a flat sheet except that it's rolled up into a tube.
这个管道,这个中空的管道,食物可以穿行其中,而它就是由许多许多上皮细胞构成的,上皮细胞一个连着一个,形成了一个平坦的细胞层,但实际上它们还在肠管中卷成管状
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