作系動(dòng)詞：

　　現(xiàn)在分詞、動(dòng)名詞短語(yǔ)作表語(yǔ)：

　　The film was moving.

　　His job was teaching English .

　　過(guò)去分詞作表語(yǔ)：

　　We were moved.

　　不定式作表語(yǔ)：

　　1）有to不定式：His work that day was to clean the blackboard.

　　2) 無(wú)to 不定式：What he should do is clean the blackboard.