A

incidentally(="by" the way)附带地，顺便：Fred said, incidentally, that he had no dinner.(顺便提一下，福来德那时说，他还没吃晚饭。)accidentally(="by" chance)偶然地：I met with an old friend of mine accidentally last week.(上星期我偶然碰到一位老朋友。)occasionally (="from" time to time, not regularly)不时地，偶尔：We get visitors here occasionally.(我们偶尔在此接游客。)subsequently(="afterwards," later) At first we thought we would go; but subsequently we learned we were needed at home.(起初,我们想离开；但随后我们得知家里需要我们。)

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