This also means having a back up plan, in case one of you is sick, you get a flat tire and have no tube, etc.

这也意味着需要一个后备计划，以防你们中的一个不舒服，你的车胎漏气却没有备胎，等等类似的事情。

youdao

He had a flat tire and needed a tool to get it off.

他车胎瘪了，需要工具把它卸下来。

youdao

1：Don’t worry about the flat tire. No sweat! I have a car phone and a set of tools in back. Just let me get my jack and tire iron, and I’ll change the tire and have you back on the road in no time!

对于Jack说来轮胎瘪了显然不是大问题，因为他有汽车电话，而且车箱里还放着一套工具。所以他要Jill别担心，换个轮胎一点儿都不费劲儿。他只要取出车后面的千斤顶和铁扳手，没一会儿工夫就会把轮胎换好，让Jill开车上路。 这里的no sweat显然表示这是轻而易举、不费吹灰之力的事儿。

youdao

In the summer, temperatures on the valley floor can reach 120 degrees and a flat tire on an open stretch of road can get you in trouble fast.

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