问题补充：
Which of the following underlined parts is different in pronunciation from others?
A. My son has got a bad habit of smoking.
B. The old man always wears his blue hat.
C. He was standing by the gate waiting for her mother.
D. When she heard the news, she laughed happily.
答案：
A. My son has got a bad habit of smoking.
B. The old man always wears his blue hat.
(答案→)C. He was standing by the gate waiting for her mother.
D. When she heard the news, she laughed happily.
解析：题意：下面加下划线的部分在发音方面哪一个与其他的不同？bad、hat、happily中a发/æ/，gate中a发/ei/.故选C
