单选题 When you speak on the telephone, you cannot use your facial (面部的) expression, eye contact and gestures to help communicate your message. Your voice must do the job.
A good voice is pleasant to listen to because it communicates a positive message. Keep in mind the following qualities of a good voice:
Speak in a voice neither too loud nor too soft. Speak louder when giving important information.
Speak slowly enough so that the listener has a chance to understand your messages without your having to repeat it. Keep in mind that as you speak the other person may be taking notes.
Pronunciation is the correct way to say a word. To avoid mispronouncing (读错音) words, you may wish to check the pronunciation of unfamiliar words in the dictionary before you use them.
People with an accent unlike yours may not understand your pronunciation of some words. You also may not understand the pronunciation of some of their words. In these cases, careful pronunciation is very important for effective communication. You may need to repeat or spell words that are unusual or easy to be misunderstood.

单选题 When speaking on the phone, the essential factor for successful communication is your ______.

【正确答案】 A

【答案解析】[解析] 根据第一段可知，在通电话时只有声音可以派上用场(Your voice must do the job. )，也就是说“the essential factor for successful communication is your voice. ”故选A。

单选题 To give important information, a person speaking on the phone should ______.

单选题 The speaker is advised to speak slowly in order to help the listener to ______.

【正确答案】 D

【答案解析】[解析] 根据文章第四段“Speak slowly enough...as you speak the other person may be taking notes. ”可知，说慢一点是为了不用重复就让对方理解你的意思，而且你说话的时候，对方可能在记笔记。故选D。

单选题 To avoid mispronouncing unfamiliar words, you are advised to ______.

【正确答案】 A

【答案解析】[解析] 根据文章第五段第二句“To avoid mispronouncing words, you may wish to check the pronunciation of unfamiliar words in the dictionary before you use them. ”可知，选A。