英语翻译
问题描述：
英语翻译
which are semi-permanently coupled into sets;these sets may be joined together to form larger trains,but usually passengers can only move around between cars within a set.This "closed"nature allows the separate sets to be easily split to go separate ways.Some multiple-unti trainsets are designed so that corridor connections can be easily opened between coupled sets; this usually requires driving cabs either set off to the side or above the passenger compartment.
答
很多多节火车是有车厢组成,车厢一般是半永久式的成套连在一起形成车厢组（车厢组一般是由独立驾驶室的尤其是电力机车）.这些车厢组再连接起来形成更大列的火车,不过一般乘客只能在一个车厢组内来回活动.这样的封闭组...