請(qǐng)將下面這段中文翻譯成英文：

　　中國(guó)五年前根本沒(méi)有高速鐵路。但是現(xiàn)在高鐵列車(chē)(high-speed trains)的票經(jīng)常很快就售罄，盡管發(fā)車(chē)間隔比較短。人們能夠很方便地以?xún)杀队诿绹?guó)火車(chē)最髙速的速度在全國(guó)周游。高速鐵路系統(tǒng)的運(yùn)菅非常成功，它運(yùn)載的乘客是全國(guó)民航 (civil aviation)系統(tǒng)運(yùn)載的乘客的兩倍。中國(guó)有世界上最先進(jìn)的、低排放的快速運(yùn)輸系統(tǒng)之一，而做到這一點(diǎn)僅僅用了五年。

　　參考譯文：

　　China didn't have a high-speed rail five years ago.But now the tickets of high-speed trains are usually sold out very quickly, even though the departure interval is quite short.And people can conveniently travel around the nation at a speed that doubles the speed of the fastest American train.The operation of high-speed rail system is very successful; it carries twice as many passengers as the nation's civil aviation system.China has one of the most advanced rapid transit systems with low emissions in the world, and it only takes five years to achieve this.

　　詞句點(diǎn)撥

　　1.但是現(xiàn)在高鐵列車(chē)的票經(jīng)常很快就售罄，盡管發(fā)車(chē)間隔比較短:“售罄”可譯 為sell out，意為“賣(mài)完了，賣(mài)光了”;“發(fā)車(chē)間隔”譯為departure interval。

　　2.人們能夠很方便地以?xún)杀队诿绹?guó)火車(chē)最高速的速度在全國(guó)周游:“以...的速度”可譯為at a speed...，speed意為“速度”;“兩倍于”即“是...的兩倍”，可譯為double,也可譯為twice。

　　3.高速鐵路系統(tǒng)的運(yùn)營(yíng)非常成功，它運(yùn)栽的乘客是全國(guó)民航系統(tǒng)運(yùn)載的乘客的兩倍:“運(yùn)栽”可用carry來(lái)表示�！氨稊�(shù)+as+many/much/large等形容詞+(比較的內(nèi)容)+as”為英語(yǔ)中表達(dá)倍數(shù)時(shí)常用的結(jié)構(gòu)，中間的形容詞根據(jù)比較的內(nèi)容來(lái)定，如比較大小則用as large as,表示“是...的兩倍大”則為twice as large as。