1.现在时:表示现在正在发生的动作或状态,常见的结构是主语+动词原形(第三人称单数加-s),如:I read books every day. He reads books every day.
2.过去时:表示过去已经发生的动作或状态,常见的结构是主语+动词过去式,如:I read a book yesterday. He read a book yesterday.
3.将来时:表示将来要发生的动作或状态,常见的结构是主语+will/shall+动词原形,如:I will read a book tomorrow. He will read a book tomorrow.
4.现在进行时:表示现在正在进行的动作,常见的结构是主语+be动词+动词-ing,如:I am reading a book now. He is reading a book now.
5.过去进行时:表示过去正在进行的动作,常见的结构是主语+was/were+动词-ing,如:I was reading a book at 8 o'clock yesterday evening. He was reading a book at 8 o'clock yesterday evening.
6.现在完成时:表示过去发生的动作对现在仍有影响或结果,常见的结构是主语+have/has+动词过去分词,如:I have read this book before. He has read this book before.
7.过去完成时:表示过去某个时间点之前已经完成的动作,常见的结构是主语+had+动词过去分词,如:I had read this book before I saw the movie. He had read this book before he saw the movie.