19. (Para. 16)avoid: v stay away from sb. or sth or not use sth You can hardly avoid meeting her if you both work in the same office (声音文件 avoid) (He's been avoiding me like the plague since our quarrel) Pattern avoid doing sth 20.(Para. 16) trace: v. find sb or sth that has disappeared by searching for them carefu lly She had given up all hope of tracing her missing daughter. I cannot trace any letter from you dated 1st June. 21.(Para. 18)pack up: put things into cases, bags, etc. ready for a trip somewhere (声音文件pack) ( Our train leaves at 9 o'clock. It's time to pack up. Since the winter vacation has started, lets pack up and spend a week in the country with our grandparents. 22.(Para. 19)come across: meet, find, or discover sb. or sth by chance (插图come) I came across this old brooch in a curio shop I came across my old college roommate in town today. 23. (Para. 20)corrode: V if metal corrodes, or if something corrodes it, it is slowly destroyed by the effect of water, chemicals etc a bitter envy that had corroded their friendship (=使他们的友谊遑到损害的强烈的忌妒) (声音文件 corrode) (The metal has corroded away because of rust) NB:该词的名词形式为 corrosion 24.(Para. 20)flood in: arrive or go somewhere in large numbers (插图food Applications flood in from all over the country (声音文件food) (Donations have been flooding in since we launched the appeal.9 19. (Para. 16) avoid: v. stay away from sb. or sth., or not use sth. You can hardly avoid meeting her if you both work in the same office. （声音文件 avoid） (=He’s been avoiding me like the plague since our quarrel.) Pattern: avoid doing sth. 20. (Para. 16) trace: v. find sb. or sth. that has disappeared by searching for them carefully She had given up all hope of tracing her missing daughter. I cannot trace any letter from you dated 1st June. 21. (Para. 18) pack up: put things into cases, bags, etc. ready for a trip somewhere （声音文件 pack） (=Our train leaves at 9 o’clock. It’s time to pack up.) Since the winter vacation has started, let’s pack up and spend a week in the country with our grandparents. 22. (Para. 19) come across: meet, find, or discover sb. or sth. by chance （插图 come） I came across this old brooch in a curio shop. I came across my old college roommate in town today. 23. (Para.20) corrode: v. if metal corrodes, or if something corrodes it, it is slowly destroyed by the effect of water, chemicals etc a bitter envy that had corroded their friendship （＝使他们的友谊遭到损害的强烈的忌妒） （声音文件 corrode） (=The metal has corroded away because of rust.) N.B: 该词的名词形式为 corrosion 24. (Para. 20) flood in: arrive or go somewhere in large numbers （插图 flood） Applications flood in from all over the country. （声音文件 flood） (=Donations have been flooding in since we launched the appeal.)