现在完成时
董闯
     Learning Aims

1.To master the meanings and usages of Past Simple Tense and Present Perfect Tense.
2.To understand the differences between Past Simple Tense and Present Perfect Tense.
3.To do the exercises correctly.
判断下列句子的时态
1.She works in a factory.2.I was doing my homework at this time yesterday.3.We are going to have a picnic this Sunday.4.They held a sports meeting last week.5.Are you helping your mother ?
一般现在时
过去进行时
一般将来时
一般过去时
现在进行时