Large trucks need to gear down going up steep hills.
大型卡车在爬陡坡时，需要换低速档。
He exchanged high gear into low one when driving on a slope
爬坡时，他将高速档换成低速档。
I didn't change down quickly enough, and stalled the motor
我没有快速换成低档，发动机熄灭了。
You have to change down when you drive up a slope.
当你开车爬坡时，得换成低速档。
To shift a motor vehicle into a higher gear.
换高速档将汽车调至较高速档
automatic mechanical transmission
自动换档机械式变速器
power assisted shift transmission
动力助力换档变速器
automatic selective overdrive
自动换档的超速传动
You must use a low gear to drive up the hill.
开车上山你要用低速档。
Use a low gear to drive up the hill.
开车上山用低速档。
The driver changed down from third to second.
驾驶员将车速从第三档调低到第二档。
Give one degree time to act before you start another.
开了一档速度之后，要等它走稳了，再换档加速。
SEQUENTRONIC, sequential automated 6-speed manual transmission with steering wheel gearshift buttons for SL 350
SL350:电控排档式6档手动变速箱，配有方向盘换档按钮
semi-automatic mechanical transmission
半自动换档机械式变速器
Going up the steep hill, the lorry shifted gears.
卡车在爬陡峭的山坡时换档变速。
YB1501 Electric & Hydraulic Control Full Power-Shift Transmisson Gearing Assembly;
YB1501电液控制动力换档变速箱
The Research and Development of YB1502 Electric-hydraulic Automatic Transmission;
YB1502电液换档变速器研究与开发
Research on Improvement of Shifting Quality of Automobile Automatic Transmission;
汽车自动变速器换档品质改进的研究