英语学习-时态

时态: 即时间和状态,其中时间分为现在时、过去时、将来时、过去将来时; 状态分为四种: 一般、进行、完成、完成进行

时间/状态	一般	进行	完成	完成进行
现在	do	am/is/are doing	have done	have been doing
过去	did	was doing	had doing	has been doing
将来	will do	will be doing	will have done	will have been doing
过去将来	would do	would be doing	would have done	would have been doing

时间
现在时: 现在发生的, do/does、is/am/are、have/has
过去时: 已经发生的, did、was/were、had
将来时: 基于现在将来要发生的, will
过去将来时: 基于过去将来要发生的, would

状态
一般式: 经常发生的动作, "我经常在七点钟起床", do
进行式: 正在进行的动作, "她正在唱一首法语歌", be doing
完成式: 之前发生的动作, "他们找到那个失踪的孩子了", hava doing
完成进行式: 正在进行的总结, "我已经连续读书两个小时了", have been doing

一般过去将来时: He told me that he would go abroad. (他之前告诉我他会出国.)
过去将来进行时: He knew that I would be living in China next month.
(他就知道我接下来一个月就会在中国生活了.)
过去将来完成时: He said he would have left for London by the end of next month.
他说第二个月末她肯定已经动身去伦敦了.)
过去将来完成进行时: I knew by July he would have been working there for 30 years.
(我知道到七月他就在那里工作整整30年了.)

一般现在时还可以用来表示客观事实, Light travels more quickly than sound.(光传播的速度比声音快.)