Can, could, and would modal auxiliary verbs are mainly used to express request in our daily interactions. But, all the three auxiliaries aren’t used for same nature of request. Let’s get clarity of meaning for confident use.
Can modal auxiliary for request
Apart from other meanings, “Can” is generally used to express :-
•Slightly forceful request,
•More basic request,
•For simple purpose or things,
It is used less polite request compare to other auxiliaries -could and would.
Examples for clarity
•Can I borrow your bike for a day ?
•Can you tell them to keep quiet for a moment ?
•Can you stop making excuses ?
•Can you switch off your phone ?
Such types of requests seem to basic or rather forceful, compare to could and would.
Request with could modal auxiliary
Usually, could modal auxiliary is used to express :-
•Less polite than would,
•More polite than can.
Examples for understanding
•I haven’t received my salary yet. Could you lend me $100 for a week ?
•I think it is going to rain now. Could you keep my mobile in your bag ?
•I don’t know much about this city. Could you guide me about major places ?
•It is too hot and humid today. Could you let me sit in your office for sometime.
In all these examples, humbleness is clearly visible and could be felt easily.
Request with would
This is the most popular modal auxiliary used for polite request. No doubt, widely preferred compare to “can and could”.
Some useful examples
•I haven’t understood it properly. Would you please explain that again ?
•I forgot to collect my luggage. Would you give me details of that bus, please ?
•To keep our environment clean is our moral duty. Would you mind helping us to clean out the park ?
Wherever we use “please” after inverted subject, comma isn’t necessary; but, comma is essential when we use at the end.
In this way, by using “can, could, and would” anyone could express request with varying degrees of politeness or humbleness.