"I played basketball yesterday" 是用英语表达 "我昨天打篮球了" 的方式。
这句话由两部分组成：主语 "I" 和谓语动词 "played"。其中 "I" 是第一人称主语，表示说话者是谁； "played" 是过去式，表示动作发生在过去。
"basketball" 是名词，表示篮球。"yesterday" 是副词，表示动作发生在昨天。
例句：
I played basketball yesterday. (我昨天打了篮球)
Yesterday, I played basketball with my friends. (昨天，我和朋友们一起打篮球)
Yesterday was a great day because I played basketball in the morning. (昨天是美好的一天，因为我早上打了篮球)