一般过去时态和现在完成时的区别：１）现在完成时是表示过去的动作与现在的联系，主要说明的是现在的情况和状态；而一般过去时则强调动作发生在过去某一时间，与现在不发生联系。
例如We haven't seen him since last year. (我们自从去年以来一直未见到他．（现在还未见到）We didn't see him last year. 我们去年没见到他（现在不一定未见到）２）现在完成时表示从过去发生一直持续到现在（包括现在）的某个动作或状态，与现在有关的时间状语连用，一般过去时表示过去某一特定（与现在无关）的时间，与具体的表示过去的时间状语连用。
例如：He has lived here since he was born .自他出生以来一直居住在这儿。
（since 自从…以来与现在有关，说明还居住在这儿。
）Liumei went to see her grandmother last night . 刘梅昨晚去看了他外婆。
（只说明昨晚）（三）值得注意几个问题：１）动作发生在过去，一直持续到说话的时候，并且还在延续时，要用现在完成时。
例如：We have studied English for two years (我们学英语两年了）２）指过去的经历，但没有表示过去的时间状语，要用现在完成时。
例如：I have been to Shanghai twice . 我曾去过上海两次．３）以When开头的特殊疑问句，要用一般过去时。
例如：When did you lose your pen ? 你什么时候丢了钢笔？４）just (刚刚）与现在完成时连用，just now (刚才）与一般过去时连用。
例如：The train has just gone. 火车刚刚离开。
The train left here just now. 火车是刚才离开。
５）since 作介词，后面跟时间名词一起作状语时，句子要用现在完成时；since 作连词，引导状语从句时，主句用现在完成时，从句用一般过去时。
He has worked in this factory since 1996.I have known him since he was a child.6 ）so far 、in the last / past …… 与现在完成时连用。
例如：So far , many countries have sent up satellites into space. In the last 30 years , our lives have changed a lot.四、学习现在完成时应注意的三个区别1）延续性动词与短暂性动词的区别2）since 和for 的区别。
3）have / has gone to 、have / has been to 、have / has been in 的区别五、短暂性动词和延续性动词转换归纳。
buy—have leave— been away fromborrow—keep die—be deadget up—be up put on—be oncome back—be back open—be opengo to town—be in town lose—be missingclose—be closed begin /start—be on fall ill / asleep— be ill / asleepcatch a cold—have a coldget /receive a letter from—have a letter fromcome to —be here / therearrive in （at）/ get to / reach——be here / therejoin the army-------be in the army/ be a soldierjoin the League-----be in the League / be a league member一、Choose the right answers.( C )1 、The twins can speak good Chinese because they _________China for 6 years.A have been toB have come toC have been inD have gone to( C ) 2 、Uncle Wang_______in factory since it opened in 1989.A worksB workedC has workedD have worked( D ) 3 、_________have you lived in Beijing ?A How soonB How oftenC How muchD How long( C ) 4 、He's _________back home since 3 days ago.A comeB gotC beenD get( D ) 5、He never has lunch at home , _____he ?A hasn'tB hasC doesn'tD does( C ) 6 、----Where is Tom? I can’t find him anywhere.----He ______ back for a holiday.A. wentB. goesC. has goneD. will go( B ) 7 、I_______ him since we ________ children.A.knew, wereB. have known, wereC. know, areD. have known,are( C ) 8 、It __________ more than two years since she left home.A. wasB. has beenC. isD. be( A ) 9 、More than two months ________ since Mr Smith came here.A.has passedB.have passedC. has pastD. have past( D ) 10、----_________has the movie ________ ?---- Ever since twenty-five minutes ago.A. How soon, begunB. How long, begunC. How soon, been onD. How long, been on火眼金睛：Correct the mistakes in the following sentences.1、Tom has got up for half an hour. been up2 、Liu Mei has joined the League for three years. been in3、The train has reached the station ince 10 minutes ago. been at4、The little girl has fallen asleep for four hours. been asleep5、When have you cleaned the classroom? It’s clean now.did clean6、How long have you caught a cold? had7、She has got ten letters from her mother since last week. had1.I ___________ (be) busy these days. I ____________ (not go) to thecinema for weeks.2.How many units ______ you _______ (learn) so far?3.4.Lily with her parents ________(go) to Sanya . They will be backin five days.5.Nobody __________(dive) in our class before.6.Alice _________(make) several friends since she ______ (come) toChina.7.________ your brother_________(drive) a horse before?8.They _______________(stay) in the park during the past threehours.补全对话：A: Hello, Zhangli ! Nice to meet you.B: Me, too! How are you ?A: Fine, ____________________? I haven’t seen yo u for a long time.B: Oh, I went to Sydney with my parents. Sydney is the biggest city in Australia.A: Really? _________________________________?B: No, I haven’t. It’s the first time for me to go there.A: That’s grea t. _________________________ ? Is it too hot?B: No, Sydney is cool. Because it’s winter now.A: _______________________________?B: First by plane, then we went to Sydney by car.A: __________________________________________?B: Yes, we had a good time. By the way, I took many photos. Would you like to see them?A: That’s wonderful ! Let’s go !。