often与usually放在句中的变化

题目

often与usually放在句中的变化
He often swim on sunday.
He usually swim on sunday.
两句话在意思上有什么区别吗?

答案

often强调频率,是指做某事的频率很高,翻译成经常
usually强调习惯,是指一般情况下会怎么样,翻译成常常.