The people of Omagh, a small town in Northern Ireland, have been complaining about a mysterious humming (发嗡嗡声的) sound that can be heard at night and bothers their sleep.

In recent weeks, the Omagh District Council has actively been trying to identify the source of a nighttime noise that several residents from all over the small Northern Ireland town have been complaining about. Unfortunately, all their efforts so far have ended in failure, leaving them with no other choice than to call in sound experts to solve the mystery. People said the sound differs from the sound of passing vehicles and can only be heard late at night, usually around 12:00 am – 01:00 am. “It’s like a vibrating noise, real loud at night, about 12 or 1 every night,” one man described the sound. While some have gotten used to it, others claim that it is affecting their night sleep and demand that something be done about it.

“Officers are currently investigating the use of specialist equipment, or a specialist company, to assist in detecting the source of the noise,” a council spokesperson told the BBC. “Due to the wide area where the sound has been reported it is difficult to find out the exact source(s).” Some of the theories being thrown around about the source of the mysterious hum range from farm or factory machinery (机械) to flying saucers. Unfortunately, local authorities don’t have much to go on as of this writing, which is why they plan to bring in sound experts. 

Interestingly, Omagh isn’t the only place plagued by a mysterious sound. For years, the English village of Holmfield has been affected by a mysterious noise that has come to be known as the Holmfield Hum. A similar phenomenon has been occurring in Windsor, a Canadian city near Detroit. That sound has been called the Windsor Hum.

1.What’s the best title of the text?

A Some Noises Are Damaging People’s Health.

B A Town in Northern Ireland Needs Sound Experts.

C Mysterious Hum Keeps Residents Awake at Night.

D Mysterious Phenomena Happens Around the World.

解析：选C。C主旨大意题。本文主要描述了北爱尔兰一座小镇上居民近一个月以来一直听到一种神秘的“嗡嗡声”，让他们彻夜难眠。故选C。

2.What can we know about the mysterious sound?

A It can be heard the whole night.

B Residents thought it sweet.

C The truth behind it is still unknown.

D It is the same as the sound of cars.

解析：选C。C细节理解题。根据第二段的“Unfortunately, all their efforts so far have ended in failure”可知，人们一直在积极努力确定夜间噪音的来源，不幸的是，到目前为止，他们的所有努力都以失败告终，即没有找到发出这种声音的来源。故选C。

3.How can the process of finding out the sound be described?

A It’s funny.

B It’s dangerous.

C It’s simple.

D It’s tough.

解析：选D。D细节理解题。根据第三段的“Due to the wide area where the sound has been reported it is difficult to find out the exact source(s).”可知，由于报告声音的区域很广，很难确定确切的来源。故选D。

4.What does the underlined word “plagued” mean?

A Bothered.

B Attracted.

C Destroyed.

D Cheated.

解析：选A。A词义猜测题。根据后面的“has been affected by a mysterious noise”和“A similar phenomenon has been occurring in Windsor”可知，多年来，英国的一个村子一直受到一种被称为Holmfield Hum的神秘噪音的影响；底特律附近的加拿大城市温莎也发生了类似的现象，因此奥马并不是唯一一个被神秘声音困扰的地方。故选A。