 Welcome to English in a minute. From home. This shape is a cylinder. I wonder what Anna and Jonathan are going to do with this. What is an eight-letter word that means hollow tube? I can't help you. I'm not firing on all cylinders. Cylinder. That's it. Thanks, Jonathan. Some engines are powered by explosions in small cylinders. When all cylinders are firing, an engine is fully powered. The idiom firing on all cylinders means something is performing well. But if you say you're not firing on all cylinders, it means you're not at your best. And that's English in a minute.