"He frequently visits his grandparents" 表示他经常看望他的外祖父母。
来源:
visit 表示看望, 来访。
frequently 表示经常, 常常。
例句:
He frequently visits his grandparents on the weekends.
(他周末经常看望他的外祖父母)
He makes sure to visit his grandparents every month.
(他确保每个月看望一次他的外祖父母)
He visits his grandparents as often as he can.
(他尽可能经常看望他的外祖父母)