一般現在時與現在完成時
　　(1)I come from Shanghai．(上海人)
　　I have come from Shanghai．(從上海來)
　　(2)You read very well．(強調能力)
　　You’ve read very well．(強調一次剛完成的動作) 外語學習網
　　(3) I forget．(一時想不起來了)
　　I have forgotten．(仍沒想起來，可能已回憶起來了)
　　(4) The book is written in simple English．(表狀態)
　　The book has been written in simple English．(表動態，已用英語寫成)
　　(5) Every time I see him，he’s been reading．(兩個動作不可能同時進行)．
　　Every time l have seen him，he’s been reading．(強調兩個動作同時進行)
　　(6) He is gone．(強調狀態)He has gone．(強調動作和時間)
　　(7) He won’t come till the play begins．(演出開始時)
　　He won’t come till the play has begun．(戲已開始)
　　(8)AfterI leave school，I’11 go to college．(兩個動作緊密相接)
　　After l have left school，I’ll go to college．(強調畢業后，兩個動作可能有間隔)
　　(9) It is a long time since I saw you last．
　　It’s been a long time since Isaw you last 這兩句話一樣，后一句是美國英語)
　　(10) Where are you?(在哪兒) Where have you been?(去了哪兒)