Fuel cells that are currently designed for transportation need rapid start-up periods for the practicality of consumer use.

燃料电池，目前用于运输需要快速启动阶段的实用性。

youdao

Start by kenneling her for short periods and then build up to a maximum of three hours at a time.

一开始让她在狗屋里呆很短的时间，以后渐渐让她能适应一次在狗屋里呆上三个小时。

youdao

My personal experience--and I don't have the science behind it to back it--is that people start to get more depressed right after the sun starts to come up for longer periods of time.

NPR: Life in the Land of the Midnight Sun