If you’ve ever kept an old machine of some kind for a long time, today’s idiom will probably be useful for you. The idiom is for something to be “on its last legs”. This expression is used when we want to talk about a machine which is old and in poor condition and very close to breaking down completely. For example:
My TV set is about 20 years old, and it hasn’t been working well recently. I think it’s on its last legs.
This computer is on its last legs. We’re going to have to buy a new one soon.
Our dishwasher finally broke down completely last night. It had been on its last legs for a while, so I wasn’t surprised.
I think the reason we use this idiom with machines is because we often say that a machine “runs” on electricity or on some other source of power. Traditionally, if something is running, it must have legs to do that with. Therefore, if something will stop running soon, its “legs” are losing power. That is just my guess, but it could be a useful way to remember this idiom.
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