1. [词根辨异] cad的异体cid1（=to fall or befall）与cid2（=to cut）同形，请判断下列单词的词根是哪一个。
accident decidable decidable excide coincide
deciduous microbicide occident homicide
2. [词海垂钓]从词典中“钓”出一串同根词吧。
circum-（=around）
3. [词义判断]-cide作为后辍，可以与许多外来语词根或词干结合。试判断下列单词的词义或词根的含义。
tyrannicide matricide fratricide insecticide
vermicide parasiticide fungicide
4. [望文生义]根据已学词缀和词根的知识推测下列单词的含义。
① undecided a.
② indecision n.
③ indecisive a.
5. [寻根问底]指出下列单词的词根并领会其词义的由来。
① incisor n.切牙；门牙
② precisian n.严守规则者；清教徒
16. claim, clam [L]=to call out喊
claim和clam都源于拉丁动词clamare，意为to call out或to shout（喊叫）。claim是不定式词干在英语中的重读形式，用来构成动词；clam是动名词词干，只出现于相应的名词和形容词中。
claim [claim=to call out呼喊→“to speak loudly for one's own interest为自己的利益而呼喊”→] v. demand as one's due or property要求；索取：We have claimed compensation for the losses from the foreign company.我们已向外国公司提出索赔要求。
▽claimer [claim;-er n.] n.根据权利提出要求者
claimable [claim;-able a.] a.可要求的；可认领的
disclaim [dis-=to undo做相反之事；claim v. 要求，索取→“to undo that of claiming做与要求或索取相反的事”→] v. deny;disavow否认；抵赖：He disclaimed his responsibility for the accident.他否认自己对事故负有责任。
▽disclaimer [disclaim;-er n.] n.否认者
declaim [de-=completely完全地；claim=to call out叫喊→“to call out or speak loudly喊话；大声说话”→] v. give a formal speech演讲：The candidates declaimed against the government. 竞选人发表演说责难政府。
▽declaimer [declaim;-er n.] n.演讲者；朗诵者
declamation [declaim的对应名词：declam=to declaim演讲；-ation n.=the act表行为→] n.① the act or art of declaiming演讲；雄辩术②formal speech正式演说：to deliver a long declamation发表长篇演说
declamatory [declaim的对应形容词：declam=to declaim演说；-atory a.=characterized by有……特点的→] a.① characterized by declaiming演说的②bombastic夸夸其谈的：long and declamatory speech夸夸其谈的长篇大论
exclaim [ex-=out出；claim=to call or shout喊→“to call or shout out喊出来”→] v. cry out suddenly from pain, anger, surprise, etc.惊叫；惊叹：“Help! Help!”she exclaimed.她大声惊叫：“快来人呀！救命呀！”
▽exclamation [ex-;clam;-ation n.] n.呼喊；惊叹
proclaim [pro-=forward向前；claim=to cry out呼喊→“to call or speak forward（before the public）向前面的公众讲话”→] v. make known before the public;declare or announce officially宣布；公告：to proclaim a new law公布一项新法令
▽proclamation [pro-;clam;-ation n.] n.宣布；公告
reclaim [re-=back回；claim=to call呼唤→“to call back (from vice, error, savagery or waste condition) (从罪恶、错误或荒废状态)召唤回来”→] v. ① reform;civilize改造；感化：We reclaimed him from vice.我们使他改恶从善。② bring under cultivation垦荒：to reclaim fields from wasteland开荒造田
▽reclaimable [reclaim;-able a.] a.可改造的；可开垦的
reclaimant [reclaim;-ant n.] n.开垦者；纠正者
reclamation [re-;clam;-ation n.] n.开垦；感化
acclaim [ac-(ad-)=to对；claim=to call out呼喊→“to call out cheerfully to somebody高兴地向某人呼喊”→] v. hail or praise publicly欢呼；称赞：His play was acclaimed as a masterpiece.他的剧本被赞许为杰作。
▽acclamation [ac-;clam;-ation n.] n.欢呼；称赞
clamour [clam=to shout叫喊；-our n.=the state表状态→“the state of shouting叫喊的状态”→] n.① shout or outcry for demand, appeal, etc.叫喊；呼声：A clamour of protest went up from the masses.群众发出了抗议的呼声。②noise made by shouting吵闹声，喧嚷：The clamour of the traffic gave me a headache.车马喧闹，叫人头痛。
