英语人教版八年级下册unit9语法聚焦

Mother: Dear , you must clean our house today?
Father: Honey, we have just(刚刚) cleaned our house.
现在完成时的结构
主语 + have/ has + 过去分词（pp）
注：主语若是第三人称单数助动词用 has
since , for 的用法:
since: (自…以来)
1)since+时间点
Take notes
He has stayed here since 5 o’clock. 2)since+ 时间段+ ago
He has stayed here since 5 hours ago. 3)since+ 从句
Mother: Dear, tell your father to have breakfast please.
Son: Mum, dad has had breakfast .
Father: Tell your mother to buy some milk, son.
Son: Oh, she has just(刚刚) bought some.
常与already(已经), yet(已经), just(刚刚),ever(曾经) 等词连用.
already: 常用于肯定句中. yet: 常用于否定句,疑问句尾.
3) 表示从过去开始并持续到现在的动作或状态，常 与包括现在在内的一段时间的状语连用。
She has learned English for 5 years. He has lived in Beijing since he was born . Has he lived in Shenzhen for 4 years?
(3)、以“辅音字母 + y ”结尾的动词，将 “y” 变为 “i”，
再加“ ed ”。 ， study---studied---studied cry---cried---cried
(4)、重读闭音节结尾，末尾只有一个辅音字母， 先双写该辅音字母，再加“ ed ”。 stop---stopped---stopped drop---dropped--dropped
常与for, since引导的时间短语或从句连用. for+ 时间段 since+时间点 , since+ 句子
注：并非所有for作为时间状语的句子都用现在完成时
I worked here for more than twenty years. (我现在已经不在这里工作了)
I have worked here for more than twenty years. （现在我仍在这里工作）
She has taught English since he came here.
for: (长达）
for+ 时间段
He has kept the book for 2 weeks.
2、不规则变化 （过去分词与不规则动词的过去式形式一样）
have—had—had spend —spent—spent make—made—maden say—said—said find—found—found hear—heard—heard
3、不规则变化 （过去分词与过去式形式不一样）
take—took—taken speak —spoke—spoken sing—sang—sung drive—drove—driven be—was/were—been go—went—gone
WintБайду номын сангаасr has already come， will it still be far in spring ?
冬天已经来了，春天还会远吗？
Present Perfect Tense
现在完成时
past
present(now)
future
现在完成时的结构 主语 + have/ has + 过去分词（pp）
否定形式 haven’t ( have not ） +过去分词 hasn’t ( has not ) +过去分词
疑问句 把助动词 have / has 放在句首
区别have 和 has的用法
You have planted all the trees. I have planted all the trees. He/she has planted all the trees. They have planted all the trees.
4、不规则变化 （过去分词，过去式与动词原形一样）
cut—cut—cut put —put—put let—let—let read—read—read
现在完成时的用法
1) 表示到现在为止已经完成或刚刚完成的动作。 Now we have planted all the trees. He has just come back. They have built many buildings in this city.
主语若是第三人称单数助动词用 has
过去分词
1、规则变化（过去分词与过去时变化规则一样）
(1)、一般动词，在词尾直接加“ ed ”。 work---worked---worked visit---visited---visited
(2)、以“ e ”结尾的动词，只在词尾加 “ d ”。
live---lived
2) 表示过去发生的动作,强调结果或对现在的影响。
Someone has broken the window. (窗户现在是坏的) I have already lost the key. (我现在没有钥匙) I haven’t read that book yet . (不了解书的内容) I have just cleaned my hands. (手是干净的)
助动词表示“有”
Winter has already come， will it still be far in spring ?
Mother: Dear son, clean your teeth please.
Son: Mum, I have already(已经) cleaned them.