just 和 just now 的区别
just now 一般用于过去时,just 用于完成时,他们在句中的位置也不一样。
We had an English lesson just now.
We have just had an English lesson.
today,this morning,this afternoon 等时间状语需根据说话时具体情况来定时态。
1He didn"t fill in the registration form this morning.今天早上他没有填登记表。
2He hasn"t filled in the registration this morning.他早上还没填登记表。
1的时态是过去时,所以早上已经过了。
2的时态是现在完成时,所以说话时还是早上,他还是可能会填表的。
注意地点状语
有的地点状语会限定时间,从而影响时态。
I bought the butter in switzerland.
虽然没有时间状语,但是“在瑞士”这个地点状语限定了动作发生在过去某时,所以不能把动作与现在联系起来。
比较:I have bought the butter.
这句包含两个意思:
1I bought the butter.
2Now I have the butter.
I joined the army in America.
“in merica”限定,只能用过去时。
比较:
join是瞬时动词,所以上面的句子要改为
I have been in the army.
此句包含两个意思:
1I joined the army some time ago.
2Now I"m soldier.