纯动词原形就是现在时态 I love my girl friend !
V+ed/动词过去式 是一般过去时态 I loved you !
will+V原形/be going to 是一般将来时
I will go to school.
have/has+done(动词过去分词)现在完成时
I have finished my homework.
She has finished her homework.
had+done(动词过去分词)过去完成时
I had finished my homework.
还有现在完成时的标志性词语:ever,never,since,already,yet,before.twice,once ,three times.