如果本地网络上有多个 DHCP 服务器可用，那么主机和 DHCP 服务器之间将按什么顺序发送 DHCP 消息？ A: acknowledgment, request, offer, discover确认、请求、提议、发现 B: request, acknowledgment, discover, offer请求，确认，发现，提供 C: discover, offer, request,acknowledgment发现、提供、请求、确认 D: request, discover, offer, acknowledgment请求、发现、提供、确认

What you can do if you want to show acknowledgment?

In MLA style, a list of the sources used in a paper that serves as a general acknowledgment of indebtedness to each.

Unit 3 Reading Comprehension Section C (2×10=20 points ) Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A), B), C) and D). You should decide on the best choice and mark the corresponding letter on the Answer Sheet with a single line through the centre.. Passage One “My adviser wants me to call him by his first name,” many foreign graduate students in the U.S. have said. “I just can’t do it! It doesn’t seem right. I have to show my respect.” On the other hand, professors have said of foreign students, “They keep bowing and saying ‘yes, sir, yes, sir.’ I can hardly stand it! I wish they’d stop being so polite and just say what they have on their minds.” Differing ideas about formality (礼节) and respect frequently complicate relationships between American professors and students from abroad, especially Asian students (and most especially female Asian students). The professors generally prefer informal relationships (sometimes, but not always, including use of first names rather than of titles and family names) and minimal acknowledgment of status differences. Many foreign students are accustomed to more formal relationships and sometimes have difficulty bringing themselves to speak to their teachers at all, let alone address them by their given names. The characteristics of student-teacher relationships on American campuses vary somewhat, depending on whether the students involved are undergraduate or graduate students, and depending on the size and nature of the school. Graduate students typically have closer relationships with their professors than undergraduates do; at smaller schools student-teacher relationships are typically even less formal than they are at larger schools. To say that student-teacher relationships are informal is not to say that there are no recognized status differences between the two groups. There are. But students may show their respect only in subtle ways, mainly in the vocabulary and tone of voice they use when speaking to teachers. Much of their behavior around teachers may seem to foreign students to be disrespectful. American students will eat in class, read newspapers, and assume quite informal postures (姿势). Teachers might not enjoy such behavior, but they put up with it. Students, after all, are individuals who have the right to decide for themselves how they are going to act. American teachers generally expect students to ask them questions or even challenge what they say. Teachers do not generally assume they know all there is to know about a subject. Nor do they assume that they always explain things clearly. Students who want clarification (澄清) or additional information are expected to ask for it during the class, just after class ends, or in the teacher’s office at the times the teacher has announced as “office hours.” Students who do not ask questions may be considered uninterested.