/ˈɑ:nsə(r); US ˈænsər ||; ˈænsɚ/verb[I,T] 1 to say or write sth back to sb who has asked you sth or written to you 回答；答复: I asked her what the matter was but she didn't answer. 我问她发生了什么事，但她没有回答。I've asked you a question, now please answer me. 我已经问了你一个问题，现在请你回答。Answer all the questions on the form. 回答表格上的所有问题。He hasn't answered my letter yet (= written a letter back to me). 他还没有给我回信。When I asked him how much he earned, he answered that it was none of my business. 我问他赚了多少钱，他回答说这不关我的事。‘No!’ he answered angrily. “不！”他生气地答道。
Answer and reply are the most common verbs used for speaking or writing in reaction to questions, letters, etc I asked him a question but he didn't answer. I sent my application but they haven't replied yet. Note that you answer a person, a question or a letter (no ‘ to ’) but you reply to a letter. Respond is less common and more formal with this meaning Applicants must respond within seven days. It is more commonly used with the meaning of ‘reacting in a way that is desired’ Despite all the doctor's efforts the patient did not respond to treatment. 回答问题、覆信等最常用的动词是 answer 和 reply：I asked him a question but he didn't answer. 我问了他一个问题，但他没有回答。I sent my application but they haven't replied yet. 我寄了申请信，但他们还没有回复。答复别人问题或回信可以说 answer a person, a question or a letter（不加 to），但是回信也可以说 reply to a letter。respond（意指“答复”）较少用，但适用于较正式的场合：Applicants must respond within seven days. 申请人须于七天内回复。Respond 通常指“有预期反应”﹕Despite all the doctor's efforts the patient did not respond to treatment. 虽然医生用了各种方法，但病人身体对治疗没有反应。 2 to do sth as a reply 以行动回复: Can you answer the phone (= pick up the receiver) for me, please? 请替我接听电话好吗？I rang their doorbell but nobody answered. 我按了他们的门铃，但是没有人应门。
answer back to defend yourself against sth bad that has been written or said about you 答辩；辩护
answer (sb) back to reply rudely to sb 回嘴；顶嘴；顶撞
answer for sb/sth 1 to accept responsibility for sth/sb 对某人或某事负责；为…承担起责任: Somebody will have to answer for all the damage that has been caused. 总得有人对所造成的一切损毁负责。
2 to speak in support of sb/sth 发言支持