Does it work?
“It could certainly work.”
“It certainly works.”
Does it, really?
Each adverb is laden with varying degrees of uncertainty, some of which depend on your understanding of English to perceive. Yet even as native English speakers, Australians and Canadians interpreted commonly used adverbs slightly differently in terms of the level of confidence each word conveyed. Imagine how much more complex it becomes when the speaker and listener do not speak the same native language. When the patient wants a straight answer and at the same time listens through a filter of hope. When the doctor has a pretty good handle but needs to be cautious.
Would it be easier if we just answered questions on a scale of 1 to 10?