- with obj. teach (a person or animal) a particular skill or type of behaviour through practice and instruction over a period of time训练（人, 动物）：
the scheme trains people for promotion
该计划提供晋升培训
with obj. and infinitive the dogs are trained to sniff out illegal stowaways.这些狗是被训练来嗅捕偷渡者的。
- no obj. be taught in such a way受训练：
he trained as a plumber.
他接受了水管工培训。
- usu. as adj. trained cause (a mental or physical faculty) to be sharp, discerning, or developed as a result of instruction or practice对（智能, 体能）进行训练：
an alert mind and trained eye give astute evaluations.
机警的头脑、敏锐的眼光能对事情进行精确评价。
- cause (a plant) to grow in a particular direction or into a required shape使（植物）朝某方向生长, 成某形状：
they trained crimson ramblers over their houses.
他们让深红色的蔓生植物爬上屋舍。
- no obj. undertake a course of exercise and diet in order to reach or maintain a high level of physical fitness, typically in preparation for participating in a specific sport or event（尤指为特定运动、活动而）进行锻炼; （通过运动、合理饮食）使自己身体状态良好：
she trains three times a week.
她一星期作三次锻炼。
- cause to undertake such a course of exercise使锻炼, 训练：
the horse was trained in Paris.
这匹马在巴黎接受了训练。
- no obj.
train down
reduce one's weight through diet and exercise in order to be fit for a particular event（为某比赛项目而）减肥： he trained down to heavyweight.
他减肥以参加重量级比赛。
- with obj.
train something on
point or aim something, typically a gun or camera, at（尤指用枪、照相机）对准, 瞄准： the detective trained his gun on the side door.
侦探把枪对准边门。
- no obj., with adverbial of direction dated go by train〈旧〉乘火车：
Charles trained to London with Emma.
查尔斯与爱玛乘火车去伦敦。
- with obj. archaic entice (someone) by offering pleasure or a reward〈古〉引诱。
- a series of railway carriages or wagons moved as a unit by a locomotive or by integral motors火车, 列车, 铁路货车：
a freight train
一辆货运列车
the journey took two hours by train.
旅行乘火车花了两个小时。
- a succession of vehicles or pack animals travelling in the same direction（沿同一方向行进的）车队, 动物行列：
a camel train.
一支骆驼队。
- a retinue of attendants accompanying an important person随从, 扈从。
- a series of connected events一系列相关的事情：
you may be setting in motion a train of events which will cause harm.
你可能在触发一系列坏事。
- usu. with modifier a series of gears or other connected parts in machinery（机械的）系：
a train of gears.
轮系。
- a long piece of material attached to the back of a formal dress or robe that trails along the ground裙裾, 拖裙。
- a trail of gunpowder for firing an explosive charge（引爆炸药用的）导火线。
in train
- (of arrangements) well organized or in progress（安排）妥当, 周密; 在进行中：
an investigation is in train.
调查正在进行中。
in someone/thing's train（或in the train of）
- following behind someone or something跟随（某人, 某事）; 随后。
- figurative as a sequel or consequence〈喻〉结果：
unemployment brings great difficulties in its train.
结果失业带来了极大困难。
train of thought
- the way in which someone reaches a conclusion; a line of reasoning思路; 推理过程：
I failed to follow his train of thought.
我没能跟上他的思路。