•I'm trying to improve my fitness by cycling to work.我每天骑脚踏车上班，想以此来改善健康状况。

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•His fitness for the new position is not in question.他胜任那个新职位，这毫无疑问。

•[+ to infinitive] Many people are concerned about her fitness to govern.由她来统辖是否合适，许多人对此表示担忧。