The problem is incomplete combustion .

燃料的不完全燃烧是主要问题。

The nozzle and bell-shaped combustion chamber have yet to be attached to this engine .

钟形喷嘴和燃烧室此时还没有被连接到这台发动机上。

Almost all cars currently use what is called afour-stroke combustion cycleto convert gasoline into motion .

当今几乎所有的汽车都使用所谓的四冲程燃烧循环把汽油转变成运动。

This means it can use oxygen from the atmosphere for combustion instead of carrying it onboard .

这意味着它可以利用空气中的氧气进行燃烧，而不必随机携带氧气。

One contains an electric charging mechanism and the other includes electric combustion piles fueled by liquid hydrogen .

一个部分是电动的充电装置，另一个包括液态氢为燃料的电燃烧堆。