Periphyton
n. [生]固著生物, 水生附著生物
??? 情景例句
you need to work at it, Grandpa.
你得常練它， 爺爺。
He is playing on the swings outside.
他正在外面蕩秋千。
Who's that boy over there?
那邊的那個(gè)男孩是誰？