1、陈述语气，它用来陈述事实，描述实际。动词可以是任何时态。可以是陈述句或疑问句。
Who was the last one to leave?最后一个离开的是谁？
2、虚拟语气，表达一个假设动作或不真实的情况。它与陈述语气相反。
虚拟语气的语法结构明显不同于陈述语气：
I would buy a house instead of a flat.如果我是个有钱人，我会买房子而不是公寓。
3、祈使语气。说话者向对方直接请求或命令时，用祈使语气，祈使语气用现在时态或将来时态。
Hand out the exercise books please.请把练习本发下去。
I want to ride my bicycle to school.我想骑自行车上学。
虚拟条件句：
条件状语从句是非真实情况，在这种情况下要用虚拟语气。
1、条件从句与现在事实不一致，其句型为：
句型1：If ＋主语＋过去时，主语＋ should (could, would, 或might) ＋动词原形
(1) If I were you, I would study hard.
(2) If it rained, I would not be here now.
2、条件从句与过去事实不一致，其句型为：
句型2：If ＋主语＋had＋过去分词，主语＋ should（could, would, 或might）＋ have ＋过去分词
(3) If the doctor had come last night, the boy would have been saved.
(4) If I had not studied hard, I would have failed in the exam last term.
3、条件从句与将来事实不一致，其句型为：
句型3：If ＋主语＋过去时/ should ＋动词原形/ were to＋动词原形，主语＋ should (could, would, 或might) ＋动词原形
(5) If it should rain tomorrow, we would stay at home.
(6) If I were to go to the moon one day, I could see it with my own eyes.
(7) If you missed the film tonight, you would feel sorry.
eg：The sun is larger than the earth.
Does Tom usually get up very early?
What a clever boy!
祈使语气表示劝告、命令、希望或禁止等,用原形动词开始,主语常被省略。 eg:Give me some candies first.
虚拟语气用来表示说话人的主观愿望或假想，而不表示客观存在的事实，所说的是一个条件，不一定是事实，或与事实相反。
eg:If I were you, I would go at once.
其中每个下面都有很多分类。本回答被提问者采纳