Marissa held open the orange envelope and let the tooth drop into the shoebox.

玛莉莎打开橘色信封，让牙齿落入鞋盒里。

As we mature, our baby teeth drop out, replaced by adult teeth.

当我们长大，乳牙脱落，取而代之的是恒牙。

He would complain of the ailments of old age, he suffered from the most insignificant economic difficulties, and he had stopped laughing a long time back because scurvy had made his teeth drop out.

他抱怨年老多病，苦于微不足道的经济困难，早就没有笑容，因为坏血病已使他的牙齿掉光了。