形容词性从句，也称为定语从句，是一种修饰名词或代词的从句，它在句中充当形容词的角色，用于限定、补充或修饰名词。定语从句可以分为两类：限定性定语从句和非限定性定语从句。在限定性定语从句中，引导词可以省略。非限定性定语从句通常用于对已知事物进行进一步描述。
限定性定语从句
- 用来限定或具体说明名词，通常不用逗号与主句隔开。
- 引导词：that, which, who, whom, whose, where
- The book that I borrowed from the library is very interesting.（我从图书馆借来的那本书很有趣。）
- The girl who is sitting next to me is my best friend.（坐在我旁边的那个女孩是我最好的朋友。）
- The car that he bought last year is very reliable.（他去年买的那辆车非常可靠。）
- The man whose daughter won the competition is very proud.（那个女儿赢得比赛的那位男士非常自豪。）
- The house where they used to live has been renovated.（他们曾经居住的那所房子已经翻新了。）
- The movie that we watched last night was fantastic.（我们昨晚看的电影太棒了。）
- The scientist whose research paper won an award will give a lecture.（那位研究论文获奖的科学家将发表演讲。）
- The restaurant where they serve authentic Italian pizza is always crowded.（那家提供正宗意大利披萨的餐厅总是人满为患。）
- The book which explains complex physics concepts is quite challenging.（那本解释复杂物理概念的书相当具有挑战性。）
- The team that won the championship last year is training hard for the upcoming tournament.（去年获得冠军的那支队伍正在为即将到来的比赛努力训练。）
非限定性定语从句
- 用来补充说明名词，通常用逗号与主句隔开。
- 引导词：which, who, whom
- My car, which I bought last year, is very reliable.（我去年买的那辆车非常可靠。）
- Mary, who is an excellent singer, will perform tonight.（玛丽是一位出色的歌手，今晚会表演。）
- His dog, whose name is Max, loves to play fetch.（他的狗，名叫马克斯，喜欢玩接物游戏。）
- The Eiffel Tower, which stands in Paris, is an iconic landmark.（埃菲尔铁塔位于巴黎，是一个标志性地标。）
- My grandparents, who have been married for 50 years, are celebrating their golden anniversary.（我祖父母结婚已经50年了，正在庆祝他们的金婚纪念日。）
- My sister, who is a talented artist, just had her first gallery exhibition.（我姐姐是一位才华横溢的艺术家，刚刚举办了她的第一次画廊展览。）
- The Great Wall of China, which stretches over 13,000 miles, is a UNESCO World Heritage Site.（中国长城横跨13000多英里，是联合国教科文组织世界遗产。）
- John Lennon, whose music continues to inspire generations, was a legendary musician.（约翰·列侬的音乐继续激励着一代又一代人，他是一位传奇音乐家。）
- The old oak tree, which has stood here for centuries, holds many stories within its bark.（这棵古老的橡树已经在这里立足了几个世纪，树皮下蕴含着许多故事。）
- My grandmother, who lived through two world wars, has incredible life experiences to share.（我祖母经历了两次世界大战，有着令人难以置信的人生经历可以分享。）