英文文法......................

現在完成式- present perfect tense (has, have + past participle)
ex: How long have you been in Australia? Oh, i have been in here for 2 years already.
在被動句(passive voice)裏, 在be (即am, is, are, was, were)之後的動詞要用past participle
past participle作形容詞有幾種用法: 1. 形容被動的事件, 如: The window is broken. A stolen car was found yesterday.

2. 形容人的心情: I am delighted. She is interested in opera.

3. 形容已完成的事件: The burnt house (燒過的房屋) the cooked food (煮過的食物)