Ex.3. Listen to the following conversation twice and fill in the blanks with the missing words. Barbara: Surely cell phones have negative effects. One of them is【填空1】You had better believe it.Tony: What do you mean?Barbara: Look at students! They play games and talk to their friends 【填空2】 on their cell phones.Tony: It's a problem, isn't it?Barbara: Sure it is. 【填空3】I'm trying to make is they don't get time for studies.Tony: Actually, cell phones are quite useful in studies. 【填空4】.Barbara: What kind of use are you talking about?Tony: For example, you can use it to get information of any subject【填空5】.Barbara: But everything has two sides.Tony: Yes. It's also important to know【填空6】of cell phones.Barbara: Especially for college students.