I can only think/suppose/assume (that)spoken used when you are giving a reason for something, to say that you do not know something for certain but think that this is the only possible reason 我只能认为/假定/假设〔用于说明唯一可能的理由〕 I can only assume that it was a mistake. 我只能假设这是一个错误。
I can only think/suppose/assume (that)• As for an Iguana Air, I can only assume it's a tropical airline.• Now if I can only think of their name.
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