动词一般现在时的用法

1.表示经常性或习惯性的动作，常与表示频率的时间状语连用。  时间状语: often, usually, always, every …, sometimes, at …, on Sundays, never等  例：I leave home for school at 7 every morning. 我每天七点钟离开家去上学。2.表示客观真理、客观存在、科学事实。  例：The earth moves around the sun. 地球围绕太阳转。      Shanghai lies in the east ofChina. 上海位于中国的东部。      He told me last week that he is eighteen. 上周他告诉我他十八岁。  注意：此用法如果出现在宾语从句中，即使主句是过去时，从句谓语也要用一般现在时。  例：Columbus proved that the earth is round. 哥伦布证实了地球是圆的。      At that time, people did not know that the earth moves. 在那个时候，人们不知道地球在运动。3.用于格言或警句中。  例：Pride goes before a fall. 骄者必败。4.表示现在时刻的状态、能力、性格、个性。  例：I don’t want so much. 我不想要那么多。      Ann Wang writes good English but does not speak well. 王安的书面英语很好，但是他的口语不好。  比较：Now I put the sugar in the cup. 现在我把糖放进杯子。        I am doing my homework now. 我现在正在做家庭作业。  第一句用一般现在时，用于操作演示或指导说明的示范性动作，表示言语的瞬间动作。  第二句中的now是进行时的标志，表示正在进行的动作的客观状况，所以后句后句用现在进行时。5.一般现在时表将来1）下列动词：come, go, arrive, leave, start, begin, return等的一般现在时表将来。这主要用来表示在时间上已确定或安排好的事情。  例：The train leaves at six tomorrow morning. 火车在明天早上六点开。      —When does the bus start? 公共汽车什么时候开？      —It starts in ten minutes. 在十分钟之后开。2）时间状语从句，条件句中，从句用一般现在时代替将来时。  例：When Bill comes（不是will come）, ask him to wait for me. 比尔来的时候，告诉他等等我。      I’ll write to you as soon as I arrive there. 我一到那里就给你写信。3）在动词hope, take care that, make sure that等后，用一般现在时表将来。  例：I hope they have a nice time next week. 我希望下周他们能够度过一个快乐的时光。      Make sure that the windows are closed before you leave the room. 离开房间之前要确保窗户都关上了。6.一般现在时代替过去时1）“书上说”，“报纸上说”等。  例：The newspaper says that it’s going to be cold tomorrow. 报纸上说明天会很冷的。2）叙述往事，使其生动。  例：Napoleon’s army now advances and the great battle begins. 拿破仑的军队现在前进，大战役开始了。7.一般现在时代替完成时1）有些动词用一般现在时代替完成时：  如hear, tell, learn, write, understand, forget, know, find, say, remember等。  例：I hear（=have heard）he will go to London. 我听说他要去伦敦。2）句型“It is … since …”代替“It has been … since …”  例：It is（=has been）five years since we last met. 上次我们见面之后已经五年没见了。8.一般现在时代替进行时  用在一些倒装句型中，表示动作正在进行。句型如：Here comes…; There goes…  例：Here comes the bus. = The bus is coming. 公共汽车来了。      There goes the bell. = The bell is ringing. 铃声响了。