在英语写作中，我们常常使用关系副词which来引导一个非限定性从句，提供额外的信息或解释前面的名词或主题。这个从句通常用逗号与主句分隔开来。
Which经常用来引导从句，说明概念或对象的特定方面，提供了对主题进行进一步解释的机会。它可以用来引出补充信息，增加语句的详细程度。例如：
- I bought a new phone, which has a powerful camera.
- He showed me his new car, which he had just purchased.
- She opened the book, which was filled with beautiful illustrations.
在上述例子中，which从句提供了关于手机、汽车和书的额外信息，帮助读者更好地理解主题。
此外，which也可用于引出定语从句，用于限定已知的信息或特定的对象。这种关系从句通常不用逗号与主句分隔开来。例如：
- The book which I am reading is very interesting.
- The house which she lives in is beautiful.
- The computer which I bought last week is already broken.
在这些例子中，which从句限定了主题的范围，使读者可以确定特定的书、房子或计算机。
