roller-coaster

柯林斯詞典

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. 過山車
It's great to go on the roller coaster five times and not be sick. 能坐5次過山車而不吐真夠棒的。
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. (指人或事急轉(zhuǎn)突變) 過山車[journalism]
I've been on an emotional roller coaster since I've been here. 自從我到這里以來，情緒像坐上了過山車。