What about the concise, memorable, and conveniently alliterative expression WHILE YOU WAIT, which is sometimes seen on business signs?
If someone can remember that three-word phrase (and the pictures I've added might help someone do just that), then it might be easier for them to remember how while would be the word that means "during some time interval."
Once you get one half of a confusing pair straight in your mind, the other half pretty much falls into place by default. But if you wanted something more, you could simply imagine the business owner saying:
I can fix this while you wait; you won't pay until I'm done.
When talking about a particular food or meal, eat and have can function interchangeably most of the time. Of the two, have is the more versatile and generic word:
Let's start with your last example:
I'm eating pizza now. Let me call you back – I don't want my pizza getting cold.
I'm having pizza now. Let me call you back – I don't want my pizza getting cold.
I see no real difference in those two statements. I think I'd be more likely to use the first, but the second wouldn't jar my native ear.
Then your breakfast example:
I eat breakfast every day at 8 o'clock.
I have breakfast every day at 8 o'clock.
Once again, either one of those is okay, although the second sounds a little bit more formal for some reason. In its seventh definition for have, Macmillan mentions:
have (verb) [TRANSITIVE] [NEVER PASSIVE] to eat or drink something. This word is often used in polite offers and requests
- Can I have another piece of that delicious cake?
- Let me buy you a drink. What’ll you have?
- Why don’t you stay and have lunch with
us?
I’ll have (=used for requesting food or drink in a restaurant): I’ll have the roast beef, please.
There are a few places where the two words aren't interchangeable. The end of that definition gives one example; if I was ordering at a restaurant, I wouldn't say, "I'll eat the roast beef, please." That might be true, if that's what I'm ordering – but it's simply not idiomatic to say it that way.
Another clue is that have is always transitive. So, it's perfectly fine to say:
I'm starving – let's eat!
but you wouldn't be able to say:
I'm starving – let's have!
Here's one more odd case:
I'm hungry; let's have at that hamburger place.
I'm hungry; let's eat at that hamburger place.
In this case, we can't use have to mean eat, because we're not using the word transitively. We can fix that by saying:
I'm hungry; let's have hamburgers at that place.
However, the first is not necessarily grammatically incorrect, because we could be using the phrasal verb have at. NOTE: This would be a very informal usage of have at, but I give it a mention because it shows how complex and flexible English can be, especially when dealing with informal expressions and eating food. When I was in college, one of my roommates might have said:
I'm hungry; I think I hear hamburgers calling my name!
Best Answer
This is a good question.
IMO, you don't need anything in that sentence though. And, I'm a non-native speaker. Though the question is not asked to us, I'd like to express what I think about the use of 'when' and 'while'. What is preferred by native speakers, they'd only answer.
But then, if it's about putting while or when...
Both 'when' and 'while' indicate time-related actions. Both the words are quite often used in sentences with past progressive and simple past tenses. In such cases, while generally refers to a comparatively long action, on the other hand, when could be both a comparatively long or short action. Also, while has a clause with a simultaneous activity or ongoing activity.
Nevertheless, when you are going from one place to another place, your smartphone will get you the Internet access while on the road. And, when your friend asks whether smartphones allow access, you may simply nod and say that smartphones allow Internet access when on the road.