A study revealed that many modern languages descended from a
1个回答

A systematic study 是主语,revealed是谓语,many modern languages 是宾语从句中的主语,

descended from a commonparent language是他的定语,lost to us 是宾语从句中的谓语,because nothing was written down 是宾语从句中的原因状语.翻译如下:

系统的研究表明许多拥有共同的祖先的现代语言之所以失传了是因为他们没有文字.