用一個句子作定語,這個句子就叫定語從句。定語從句通常緊靠在它所修飾的名詞或代詞后面。定語從句相當于一個形容詞,用來修飾名詞、代詞或句子。
1.從句謂語的數須與先行詞一致
定語從句中的謂語動詞須與主句中的先行詞在人稱和數方面保持一致。如:
The recorder that has been given to me is home-made.給我的那一臺錄音機是國產的。
I didn't meet the guests who were here last week。我沒有會見上星期在這里的客人。
注意:
有時先行詞與關系代詞隔開,這時先確定先行詞,然后判斷單復數。如:
①Henry is doing experiments in the laboratory which are important to his studies of certain chemicals.亨利正在實驗室里做試驗,這些試驗對于他研究某些化學藥物是很重要的。(which的先行詞只能是experiments,而不是緊處在它前面的laboratory,因為重要的只能是“試驗”,而不是“實驗室”。因此which應當是復數。)
②Peter and John often take their aunt in a car to the parks which has been given to them as a present.彼得和約翰經常開車帶他們的姑媽到公園去,這輛車是(姑媽)送給他們的禮物。(which指的是單數的car,而絕不是復數的parks,因為car才能作為送給人的禮物。)
2.主句謂語要和主語的人稱和數一致
主句的主語和謂語動詞在人稱和數方面要與主句保持一致,而不是從句。如:
I ,who am your colleague ,will share the work with you.我是你的同事,要和你分擔這項工作。
He ,who is my neighbour ,has a deep sympathy for me.他是我鄰居,非常同情我。
They ,who are here now ,are not aware of the danger.他們在這里,沒有覺察到危險。
3.關系代詞what作主語時的主謂一致
關系代詞what作主語時,動詞的數要與what所表示的數的概念一致。如:
We are satisfied with what has resulted from the experiment.
we are satisfied with the thing which has resulted from the experiment.我們對試驗中得到的結果感到滿意。
Our grocery will sell what are most welcomed by the customers.
Our grocery will sell goods which are most welcomed by the customers.我們的雜貨店要出售最受顧客歡迎的商品。
4.關系代詞which作主語時的主謂一致
關系代詞which作主語指的是它前面的整個主句時,動詞要用單數。如:
He jumped for joy at the news,which was natural.他聽了這個消息高興得跳起來,這很自然。
5.one of 結構中的主謂一致
在“one of the+復數名詞(短語)”中,從句的動詞通常用復數。如:
This is one of the questions that have been raised by the audience.這是聽眾提出的許多問題中的一個問題。(復數)
注意:
當“one of the+復數名詞”這個短語前有the,the only,the very時,關系代詞所代表的是一個單數的概念。如:
The schoolmaster is the only one of his short stories that is not well written.《校長》是他唯一的一篇寫得不好的短篇故事。(單數)