train (n.) 火车
例句:traveling by train is very convenient in europe.在欧洲用火车来旅游是非常方便的。
be at a 1 需求量很大;奇缺
例句: tickets for the football match were at a premium.那场足球赛的门票需求量很大,很难搞到手。
i'm working on it.我正在努力。
对话:a: albert, do you drive? b: no, but i'm working on it.
a:albert,你会开车吗? b:不会。我正在学。