In a discussion at work, someone suggested an idea that sounds good. But in reality, you don't think it can be done. You want to say that in a direct but polite way. You say:
From a practical perspective, I don't see how that's possible.
You can think about an idea in many ways. You can think about how much it costs, or how long it takes, or how beautiful it is. When you talk about an idea and want to explain how you're thinking about it, you use "from a ___ perspective" at the beginning or end of your sentence:
It makes sense from a business perspective, but for consumers it's not very easy to use.
This means that you don't understand something or don't agree with it. For example, if you're waiting for a long time on an airplane for it to take off, you can say to the person who's riding with you:
I don't see what's taking so long.
This means that you don't understand why it's taking such a long time, and you're angry about it. So "I don't see ___" is used when you don't understand the reason for something and you don't think that there really is a good reason.
Here are some more examples with different endings:
I don't see why not.
I don't see what the big deal is.
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