More and more residences, businesses, and even government agencies are using telephone answering machines to take messages or give in formation or instructions. Sometimes these machines give 【C1】______ instructions, or play messages that are difficult to understand. If you 【C2】______ telephone calls, you need to be ready to respond when you get a 【C3】______ The most common machine is the 【C4】______ used in residence. If you call a home 【C5】______ there is a telephone answering machine 【C6】______ you will hear several rings and then a recorded message that 【C7】______ says something like this: 'Hello. We can't come to the 【C8】______ right now. If you want us to call you back, please leave your name and number after the beep.' Then you will hear a 'beep,' 【C9】______ is a brief, high-pitched 【C10】______ . After the beep, you can say who you are, whom you want to speak to, and what number the person should call to 【C11】______ you, or you can leave a 【C12】______ . Some telephone answering machines record for only 20 or 30 seconds after the beep, 【C13】______ you must respond quickly. Some large businesses and government agencies are using telephone answering machines to provide information on 【C14】______ about which they receive a large volume of 【C15】______ Generally speaking, using these systems 【C16】______ you to have a touch-tone phone. The voice on the machine will tell you to 【C17】______ a certain button on your telephone if you want information on Topic A, another button for Topic Band and so on. You listen 【C18】______ you hear the topic you want to learn about, and then you push the 【C19】______ button. Immediately after making your 【C20】______ , you will hear a recorded message on the topic. 【C1】