white elephant
noun /ˌwaɪt ˈelɪfənt/
/ˌwaɪt ˈelɪfənt/
[usually singular]- a thing that has no use and is no longer needed, although it may have cost a lot of money
昂贵而无用之物 - The new office block has become an expensive white elephant.
这座新办公大楼成了昂贵的摆设。
词源From the story that in Siam (now Thailand) the king would give a white elephant as a present to somebody that he did not like. That person would have to spend all their money on looking after the rare animal. - The new office block has become an expensive white elephant.