A supposition in grammar refers to an assumption or a belief that is taken for granted and expressed through language. It typically relates to conditional statements where a hypothetical situation is presented. For instance, in the sentence, ‘If I were rich, I would travel the world,’ the supposition is that the speaker is not rich, but is exploring what would happen if they were.
Suppositions allow us to discuss possibilities and hypothetical scenarios, often using words like ‘if,’ ‘suppose,’ or ‘assuming that.’ They help in constructing sentences that convey uncertain or unreal situations, allowing speakers and writers to express their thoughts more creatively and complexly.