We have every reason to refuse.我们完全有理由拒绝。
Can you tell me the reason why you were late this morning.你能告诉我今早为什么迟到。
reason是理由和原因的意思。再来一个例子:
We have reason to believe that he was lying.我们有理由相信他是在撒谎。
reason也可表示道理,情理。
Why didn't you listen to reason?你为什么不愿听从道理?
reason也可做动词,表示讲理,和某人讲理就用介词with.
There is no use reasoning with him.和他讲理根本没用。