Rack one's brain
rack one's brain /ræk/
绞尽脑汁，努力思索
This phrase means that someone tries every way to think about something.
这个短语用来形容想尽办法、费尽心思去思考一件事情。
He racked his brain for hours to solve the puzzle.
他绞尽脑汁想了好几个小时，试图解开这个迷题。
He racked his brain for a long time trying to figure out why his girlfriend was so angry, but failed.
他拼命想了好久都不知道他女朋友为什么那么生气。
