1) 经常性或习惯性的动作，常与表示频腮度的时间状语连用。 时间状语： every…, sometimes, at…, on Sunday I leave home for school at 7 every morning.
2) 客观真理，客观存在，科学事实。 The earth moves around the sun. Shanghai lies in the east of China. 3) 表示格言或警句中。 Pride goes before a fall. 骄者必败。
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..
4) 现在时刻的状态、能力、性格、个性。 I don’t want so much. Ann Wang writes good English but does not speak well. 比较：Now I put the sugar in the cup. I am doing my homework now.
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，表示言行的瞬间动作。再如：Now watch me, I switch on the current and stand back. 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，所以后句用一般现在时。
11.2 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。 时间状语有：yesterday, last week, an hour ago, the other day, in 1982等。 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。 When I was a child, I often played football in the street. Whenever the Browns went during their visit, they were given a warm welcome.
3）句型： It is time for sb. to do sth "到……时间了" "该……了" It is time sb. did sth. "时间已迟了" "早该……了" It is time for you to go to bed. 你该睡觉了。 It is time you went to bed. 你早该睡觉了。