They look__(sad)when they sing a happy song(用所给单词的真确形式填空,并翻译全句)

问题描述:

They look__(sad)when they sing a happy song(用所给单词的真确形式填空,并翻译全句)

sad
他们唱着一首旋律很愉快的歌,但是他们看起来很忧伤