Both “can” and “could” can be used for requests, but “could” adds a layer of politeness and indirectness, making it more appropriate in formal or sensitive situations.
Think of “could” as testing the waters – you're open to their answer, maybe even expecting they might be busy. “Can” jumps right in, assuming they’re ready to lend a hand.
Can you help me with this problem?
= less polite,
= because you are expecting the person to help you
Could you help me with this problem?
= more polite,
= because you are not sure if the person wants to help youTip
The past simple tense can sometimes be used to soften or indirectly express requests or suggestions, making them sound more polite than using the present tense. This is because the past simple can create a sense of hypotheticality or uncertainty, even if the situation being referred to is actually real or certain.
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