第三人稱單數(shù)：roofs；現(xiàn)在分詞：roofing；過去式：roofed；過去分詞：roofed。

　　例句：

　　We could see the stars through an opening in the roof.

　　我們從屋頂?shù)男《茨芸匆娦切恰?/p>

　　The stone made a dent in the roof of the car.

　　石頭把車頂砸了個坑。

　　The roof of the tunnel fell in.

　　隧道頂部塌了下來。