Pearlsgrowinsideshel的精選

問題詳情：閲讀短文並根據其內容回答問題。簡要回答，不準照抄原文中的句子   Pearlsgrowinsideshellfish（貝類動物）.Shellfishhavehardshells.Theyopenandclosetheirshellstocatchtheirfood.Theirshellsareusuallygreya...