strong英语人教版八年级下册过去进行时中的when和while的用法区别

2021年1月10日发(作者：乔迁)
Period 3 Section A Grammar focus
Teaching Aims:
Students sum up the usage of when and while in the past progressive
tense by observing the different context and can use them correctly.
Teaching Procedure:
Step 1 lead-in
Present two sentences from the textbook with when and while.
Ask students if they can tell the differences between when and
while in past progressive tense.
Step 2 Presentation
1. Present two sentences with when and fill in the blanks to
conclude the usage of when.
① I was walking to school when I saw a cat in a tree.
② When Sally arrived home, her mother was cleaning the house.
主句的动作是持续性的，而从句动作是短 暂性的，此时用
_______引导时间状语从句，主句用_____________时态，
从句用一般过去时态。
2. Present sentences with while and fill in the blanks to
summarize the usage of while.