roller-coaster

柯林斯词典

1. N-COUNT A roller coaster is a small railway at an amusement park that goes up and down steep slopes fast that people ride on for pleasure or excitement. 过山车
It's great to go on the roller coaster five times and not be sick. 能坐5次过山车而不吐真够棒的。
2. N-COUNT If you say that someone or something is on a roller coaster, you mean that they go through many sudden or extreme changes in a short time. (指人或事急转突变) 过山车[journalism]
I've been on an emotional roller coaster since I've been here. 自从我到这里以来，情绪像坐上了过山车。