become的過去分詞是什么

　　Wearing fur has become unfashionable.

　　穿裘皮服裝已經(jīng)變得不流行了。

　　The reforms have recently become law.

　　這些改革最近已成為法律。

　　His hospital room had become a prison.

　　他的病房變成了牢籠。