1. [词根辨异]我们又遇到一对异源同形根：tent1（tendere的动名词词干，意为to stretch）和tent2（tenere的动名词词干，意为to hold）。请指出下列单词词根的含义：
attention retention detention ostentation
abstention sustention distention (=distension)
2. [词根辨识]在下列各对异源同形词中，有一个是本族词。请根据词义与词根含义的关系，指出这个本族词。
① tender1 a.柔软的 tender2 v.提出；提供
② tent1 n.帐篷 tent2 n.深红色葡萄酒
③ tense1 a.紧张的 tense2 n.时态
3. [同义相连]将左栏中的单词和右栏中相对应的词义连接起来。
① hypertension a.[解剖学]伸肌
② tensometer b.高血压
③ extensor c.张布架
④ tentage d.张力计
⑤ tenter e.帐篷；宿营装备
4. [由此及彼]根据已知单词的词义推断出其同根词的词义。
① extensible a.可延伸的；可扩展的→inextensible a.
② pretentious a.自负的；矫饰的→unpretentious 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 tend v.照管；服侍；招待
tender n.照料人；看管人
tendance n.照料；服侍；看护
② protend v.（使）伸展；（使）伸延
protensive a.延长时间的；延长的；伸长的
③ superintend v.监督；主管；指挥
superintendence n.监督；主管；指挥
superintendent n.监督人；主管人 a.监督的
④ intensifier n. [物] 增强剂
intensification n.增强；强化
93. tract [L]=to draw拉，抽
词根tract的意思与tend正好相反，它来自拉丁动词trahere的动名词词干，意为to draw（拉，抽）。在英语中，tract直接作为名词，意思为“一片土地”，“地带”。
attratct [at-(ad-) = towards 向；tract = to draw 拉→] v. draw towards oneself吸引：A magnet attracts iron.磁石吸铁。
▽attraction [attract;-ion n.] n.吸引；吸引力
attractive [attract;-ive a.] a.有吸引力的
contract [con-(com-)=together一起；tract=to draw拉→“to draw together拉在一起”→]Ⅰv.① draw together and become more compact收缩：Cold contracts metals.金属遇冷收缩。② draw (two sides) together to make a legal agreement缔结（条约）；订立（合同）：The two countries contracted an alliance.两国缔结了盟约。→Ⅱn. a legal agreement that draws together two sides契约；合同：to sign a contract签订契约
▽contraction [contract v.;-ion n.] n.收缩；缩约词
contracture [contract v.;-ure n.] n. [医学]挛缩
contractive [contract v.;-ive a.] a.收缩的；有收缩性的
contractual [contract n.;-u-;-al a.] a.契约的
extract [ex-=out;tract=to draw抽→]Ⅰv.① draw out or pull out抽出；拔出：to extract a bad tooth拔掉坏牙②draw out or obtain by squeezing抽取；榨取：to extract juice from sugarcanes 从甘蔗榨出糖汁③ draw out or copy imformation from a book, etc.摘录；引用：to ex-tract a passage from the story 从故事中选出一段→Ⅱn.① anything drawn out 抽出的东西：beef extract 牛肉汁 ② passage copied out摘录：extracts from newspapers报刊摘录
▽extraction [extract;-ion n.] n.抽出（物）；提出（物）；摘要
extractive [extract;-ive a.] a.抽出的；提取的
retract [re-=back回；tract=to draw抽→] v.① draw back or draw in抽回；缩进：The cat retracted its claws.猫把爪子缩了回去。② draw back or take back (a remark, promise, etc.)收回；取消（意见、诺言等）：He retracted the insult and apologized.他收回无礼之词并赔礼道歉。
▽retraction [retract;-ion n.] n.收回；撤消；缩回；缩进
retractive [retract;-ive a.] a.缩回的；易缩回的
retractile [retract;-ile a.] a.（爪等）能缩回的；收缩的
detract [de-=away去；tract=to draw抽→] v. draw away or take away a part of (value, reputation, etc.) 减损；贬低：The criticisms do not detract from his merit.批评并不贬低他的功绩。
▽detraction [detract;-ion n.] n.减损；贬低
detractive [detract;-ive a.] a.减损的；贬低的
distract [dis-=apart分开；tract=to draw抽，牵引→] v. draw apart (the mind), or divert (the attention)引开（心思）；分散（注意力）：The noise distracted me form reading.吵闹声使我无法专心读书。
▽distraction [distract;-ion n.] n.精神涣散；精神错乱
protract [pro- = forward 向前；tract = to draw 拉→“to draw the time forward把时间向前拉”→] v. prolong拖延，延长：Can you protract your stay for two days?你能在这儿多呆两天吗？
▽protraction [protract;-ion n.] n.延长；拖延
subtract [sub- = under, down 下；tract = to draw 拉→“to draw down a quantity把数量拉下”→] v. take away by deducting去掉；减去：to subtract the expenditure裁减开支
▽subtraction [subtract;-ion n.] n.减去；减法运算
subtractive [subtract;-ive a.] a.减少性的；带负号的
subtrahend [sub-;trah;-end n.] n.减数
