约1340字。

　　Unit 11 Working with Animals学案
　　一. 教学内容：
　　Unit 11 part 1
　　继续学习现在完成时来描述经历
　　二. 教学重点：
　　  1. 现在完成时中ever, never 的使用。
　　  2. 现在完成时中的两种动词的使用。
　　  3. 现在完成时与一般现在时，一般过去时的区分。
　　  4. 重点词组。
　　三. 具体内容：
　　（一）Present perfect with ever and never.
　　e.g.
　　Have you ever seen a polar bear?
　　I have never seen a polar bear.
　　Have you ever forgotten your homework?
　　No, never.
　　I’ve seen a dolphin, but I’ve never seen a whale.
　　（二）Two types of verbs in the present perfect.
　　  1. There are two types of verbs in the present perfect. One type refers to an action that starts in the past and continues to the present. The time phrases with for or since are used with this type of verbs.
　　e.g.
　　He has had the book for three weeks.
　　I have worked here for two months.
　　He has been a teacher for ten years.
　　They have lived in Canada since 1997.
　　He has taught me since I came to this school.
　　注意：for + 时间段 如：for ten years
　　since +时间点如：since nine o’clock
　　since + 时间段 + ago：since ten years ago
　　since + 一般过去时态从句(主句是现在完成时)
　　e.g.
　　(1) They have lived in China _____ 1998.
　　(2) We have studied English _____ 5 years.
　　(3) Joy _____  ______  (learn) Chinese since she _____ (come) to China .
　　2. The other type refers to an action that took place at a specific time in the past and cannot continue. Usually, for or since are not used.
　　e.g.
　　He has bought a book.
　　The film has begun.
　　I have borrowed a book from the library.
　　注意：瞬间动作不能与表示一段时间的短语连用，应改用持续性动词。
　　常见的瞬间动词与持续性动词的转换。