change down
phrasal verbchange down (from something) (into/to something)
- (British English) to start using a lower gear when you are driving a car, etc.
（开车等）换低一挡，换成低速挡，降挡 - Change down into second.
把车降到第二挡。 - to change down from fourth (gear) into third
从第四档（档位）降到第三档
- Change down into second.