Hello Tie, The past tense is formed by adding "ED" to the verb in infinitive in case of regular verbs such as : work becomes worked , like becomes liked , etc . There is a list of irregular verbs and their conjunction in past tense ,that you have to learn by heart or practice such as do becomes did , make becomes made etc ... The tense is used in general to indicate actions that terminated in the past . Usually this tense is mixed up with the present perfect tense which indicates an action that has JUST terminated in the present or in the near past and formed by using verb to have + any verb in Particip For example : He has just finished his lunch .( Present Perfect because the action started in the past which could be a while ago in the example and finished just in the near past. Yesterday he had his lunch at 2 pm . (Using the Past tense (had) for the action of having lunch terminated totally in the past (yesterday). Check this link for a detailed explanation of the tense and some exercises: http://www.englishpage.com/verbpage/simplepast.html :)