When the gas is made very hot inside the rocket, it will rush out of the end of the rocket, so it can make the rocket fly up into the sky.
When the gas is made very hot inside the rocket, it will rush out of the end of the rocket, so it can make the rocket fly up into the sky.
当气体在火箭里达到高温的时候，它就会冲出火箭的尾部，因此就使火箭直上云霄。