怎样判断英语句子的时态？ （从意义结构等方面） 急！在线等！！

一般情况下看时间状语
一、一般现在时 表示一般状态、习惯动作、客观规律和永恒真理
二、现在进行时 表说话时或目前一段时间内正在进行的活动；或表感情色彩,加强浯气.
三、现在完成时 表目前已完成的动作,强调对现在的影响.时间是算到你说话的时候为止,而且现在完成时有一些标志性的时间状语： 1．for+时间段；I have learned English for ten years． 2．常见的副词：lately；recently, just,up to now, till now, so far, these days, in the past few years／months／weeks／days 3．注意：for+时间段；since+时间点 They have lived in Beijing for five years． They have lived in Beijing since l995． 4．This is the first time that I have watched stars through a telescope． 第几次做某事,后面跟现在完成时.
四、一般过去时 表在过去某个特定时间发生且完成的动作,或过去习惯性动作,不强调对现在的影响,只说明过去.常跟明确的过去时间连用,如：yesterday；last week；in 1945,at that time；once；during the war；before；a few days ago；when,注意： 1、used to+动词原形,表过去经常但现在已不再维持的习惯动作. He used to smoke． 2、be／become／get used to+动名词doing,表习惯于 He has got used to getting up early． He used to smoke a lot. 3、They have lived in Beijing for five years． 用现在完成时表示到目前是5年. He lived in Japan for five years as a middle-school student. 用一般过去时则表示这个时间段和现在无关,只表示他过去在日本住了5年.
五、过去进行时 表示过去某个时间点或某段时间内正在发生的动作. The boy was doing his homework when his father came back from work． He was taking a leisurely walk by the lake when he heard someone shouted for help． 六、过去完成时 表示过去某个时间之前已经完成的动作,句中有明显的参照动作或时间,before,after,by,up till There had been 25 parks in our city up till 2000． By the end of last term we had finished the book． They finished earlier than we had expected.
一 ,一般现在时的用法
1） 经常性或习惯性的动作,常与表示频度的时间状语连用.时间状语： every…, sometimes,　at…, on Sunday.例如： I leave home for school at 7 every morning.
2） 客观真理,客观存在,科学事实.例如： The earth moves around the sun. 3 现在时刻的状态、能力、性格、个性.例如：I don't want so much. 我不要那么多. Ann writes good English but does not speak well. 安英语写得不错,讲的可不行.
二, 一般过去时的用法
1）在确定的过去时间里所发生的动作或存在的状态.例如：时间状语有：yesterday, last week, an hour ago, the other day, in 1982等.例如： Where did you go just now?
2）表示在过去一段时间内,经常性或习惯性的动作.例如： When I was a child, I often played football in the street. 我是个孩子的时候,常在马路上踢足球.
三, 一般将来时 将来某一时刻将要发生的动作或状态I will come to see you tomorrow.
2）be going to do a. 主语的意图,即将做某事.例如：W

根据时间状语和上下文及语义来判断