He had a bar of chocolate 跟 He has had a bar of chocolate
都是可以表示 “他刚刚吃了一块巧克力”这个意思的.
在英文中,He had a bar of chocolate 表示他在过去的某段时间已经 吃完了一块巧克力.而 He has had a bar of chocolate 则用现在完成时表示他刚才刚刚吃完了一块巧克力.
所以,He has had a bar of chocolate 他刚刚吃了一块巧克力 ,这个会更贴切有些.