我不得不换乘两次飞机才能到达这里。

I had to ___change planes twice to get here.

乘坐快车到市区，然后在第十四街换乘L线列车。

Take the express downtown and ___change to the L at Fourteenth Street.

你必须在奥尔巴尼换乘火车去波士顿。

You have to ___change trains in Albany for Boston.