有读者提出现在完成时如无for（经历）或since（自从）所引导的状语所修饰，其所表示的动作是否会延续下去这样的问题。
一般来说，如果没有for或since引导的状语，现在完成时所表的动作或状态，皆已完成或结束，只是其结果仍影响于现在。如：
(1)He has gone . （动作已结束，含义是 “He is not here now.”）
(2)She has been ill. （病的状态已结束，含义是“That's why she looks pale.”）
但不可绝对化，例外还是有的，虽然为数较少。比较常见的情况有下面两种：
1. 在连词since引导的状语从句中，完成时态所表的动作或状态有时仍在延续，如：
(3)There have not been many visitors since we have lived here.
(4)He has visited me quite often since I have been ill.
(5)I have gone camping twice since I have owned a bike.
(6)Her English writing has improved a lot since she has kept a diary in English.
(7)He has been grey-headed ever since I have known him.
上面5例中since之后的现在完成时所表的动作或状态显然仍会延续下去，但应注意：5例中，这些完成式动词都是持续动词（或叫做无限动词）；since在此有from the beginning的含义。
这是不是说since从句中的现在完成时所表的动作都会无例外地延续下去呢？ 事实并非如此。试举两三个例外如下：
(8)It's a long time since I have seen you. （注意see不是持续动词）
(9)It's an age since you have been here.
(10)It is now four years since I have studied this question. （如将since代之以that, have studied当然会延续下去，因为全句已变为强调结构）
2. 据一位英语学家说，英语里只有continue一词的完成式可以表示其动作或状态仍在延续，如：
(11)In the Philippines the typhoon has continued north.
动词remain的意思是continue to be，所以它的完成式亦可表延续下去的动作，如：
(12)He has remained neutral.
有一位读者问到，现在完成时如与for（经历）或since（自从）连用，它所表示的动作是否必然要延续下去。
回答是否定的。应该承认，具有for或since引导的状语的现在完成时所表的动作往往会延续下去，但也应指出，在一定的上下文中，它所表示的动作并不再延续，如：
(13)Have you waited long? （long=for long）
(14)I've lived here since I was nine, but now I'm going away.
