2022-2023学年人教版英语八年级下册现在完成时（易懂版本）

现在完成时 一、两个含义: ①表示动作发生在过去，但对现在的情况造成了影响。（借古讽今） He opened the door. The door is open. I saw the movie. I have seen the movie. I got married. I have got married. ②表示从过去某一时间开始一直延续到现在并还可能继续延续下去的动作，用于延续性动词，且句中常带有表示一段时间的时间状语，如:since + 时间点/从句，for two months, so far等。（从古至今） I have learned English for 10 years/since 10 years ago. I have lived in Chengdu for 12 years/since 12 years ago. I have been a teacher for 2 years/ since 2 years ago. 二、构成 have/has+动词的过去分词（done） 三、标志词 for, since, already, yet, before, recently, over the …., in the past few….. 四、already与yet的区别 already用于肯定句（已经） yet用于否定句（还）和疑问句（已经） ever & never ever作副词，意为“曾经”，常用于现在完成时的一般疑问句和肯定句中，置于主语之后，过去分词之前。 never作副词，意为“从不；从未”，用于现在完成时中，表示否定，位于助动词have/has之后，过去分词之前。 五．have been to & have gone to & have been in have been to 去了某地，已回 have gone to 去了某地，未回 have been in 在哪里待了多久 后面是地点副词there、here、home 时，省略to 六、延续性和非延续性 1. 含义： 延续性动词表示能够延续的动作，这种动作可以延续下去或产生持久影响。 非延续性动词也叫终止性动词、瞬间动词等，表示不能延续的动作，这种动作发生后即刻停止。 2. 用法： ①常见的延续性动词有learn, work, live, know, walk, watch, sleep, stay, wait, keep等。 延续性动词可以用在现在完成时中与表示一段时间的状语连用，如how long，for＋时间段，since＋过去的时间点，since引导的时间状语从句(一般过去时)，since＋一段时间＋ago等。 ②常见的非延续性动词有open, close, die, begin, come, go, borrow, lend, buy, move等，可以用于现在完成时，说明某个动作的结果还存在， 但不能与表示一段时间的状语连用。 ③在否定句中，非延续性动词可以与表示一段时间的状语连用。 3.for &since区别 “for+时间段” “since+过去的时间点或从句”或“since+一段时间+ago”。 4.非延续性动词（短语）与延续性动词（短语）的转换： ①直接转换成延续性动词 buy → have borrow → keep put on →wear catch a cold → have a cold 例：She caught a cold three days ago. =She has had a cold for three days. ②转换成“be＋形容词/副词/介词/名词”等 come/arrive/go → be in/at begin/start → be on finish/end/stop → be over open → be open die → be dead leave → be away close → be closed fall asleep → be asleep fall ill → be ill become → be join → be a member of/be in come back → be back go to school → be a student 例子： I have finished the work already. I have seen the movie already. I have learned English for 5 years. since 5 years ago. It is/has been ten ye