Stress should fall on the word or phrase to be emphasized. Listen to the following sentences.

1. 
   Wáng Xiānsheng shì qùnián huí Běijīng de.
   王先生是去年回北京的。
   Mr. Wang returned to Beijing last year. It was last year that Mr. Wang returned to Beijing.


2. 
   Jīntiān tā shì bú shì zǒulù lái xuéxiào de?
   今天他是不是走路来学校的？
   Was it on foot that he came to school today?


3. 
   Zhèi jiàn shìqíng shì lǎoshī gàosù wǒ de.
   这件事情是老师告诉我的。
   The teacher told me about it. It was the teacher who told me about it.