YOU COULD DO MORE THAN ONE THING AT A TIME
We have kept reminding ourselves that one thing at a time instead of keeping our concentration switching from one thing to the other, then nothing could be done at last. But we could do more than one thing at a time if energy and attention is well distributed among the things happening simultaneously.
First of all, we should make it clear what kind of things could be done together without having negative impact on one another, and how they may fit with each other.
We do some of the things out of physical memory, without need of thinking or analysis. And this kind of thing could be done together with those in need of judgment and thought to get done. We may find it is easy to do the cleaning while listening to English FM and know what the host is talking about, but it is not the case when you listen to the same program while doing some calculation or writing the logical frame of an article. You may find that it is hard to do the job requiring high concentration and accuracy well while you try to follow up the specific content of the program. Since we are energy limited, and our attention can't manage to do the things demanding your focusing on them concurrently, so our brain will optionally drop part of the attention for one thing so as to make sure that it is enough to get the other going on, or you get the worst ending where neither of them is managed well finally. You may choose to listen to the English FM while working on a project, only if you don't mind how much of the information you are able to get from the program but just the voice slipping by around your ears, getting you familiar with how English is pronounced or sounds is enough.
We could put the things doing for pleasure or relaxation without particular purpose with those needing some of the conceptual work but not getting your brain full occupied. For example, we may listen to the music while we do some reading, or have a glance on the app to see what's new and get it stored for later study the moment we are practicing spoken English.
We get something done solely by hands, or eyes, or ears, or mind, but your hands, eyes, ears and mind could basically work together. And that is to say, you can do 4 things at the same time if each of them just needs the response of a certain part mentioned above. Say, I could do the skin care while listening to audio book, with my eyes on the electronic novel set as automatically page turning, and my mind considering how to write the book review with the certain lines I read attractive to me.
If things could be arranged together according to the amount of attention needed, we could get double tasks done in the time required while the same period could be saved for something else, guaranteeing a high efficiency of time application. And that's why someone can do the things in an hour supposed to be finished in two. If you could do this, you are living in more than 24 hours a day.