英语翻译Present perfect tense:l've had a letter…He has invited u

英语翻译Present perfect tense:l've had a letter…He has invited u The present perfect tense present perfect tense,past perfect tense 用present perfect tense ,simple past tense , present continuous tense 跟present perfect continuous tense的混 the present perfect tense的中文 英语翻译Danny is learning the present perfect tense at school.Th 英语翻译As you can see,the present perfect tense is formed with 英语翻译：He has finished a third letter. 请问present/past perfect tense 跟present/past perf A ;l 've got a letter from a friend . He saw a koala.B 'The Present perfect tense和 simple past tense 有什麽区别呢 要羡怎麽用呢 例如这题该