1. access/excess: access名詞為「方法，途徑」，excess名詞為「過量」。
ex.The only access to the village is by boat.
(到達那個村落的唯一途徑就是搭船。)
ex.Inflation results from an excess of demand over supply.
(通貨膨脹是供過於求的結果。)
2. affect/effect: affect動詞語意為「影響」。effect名詞語意為「效果，影響」，但動詞語意為「使…發生, 實現, 完成」。此組單字為學生最常誤用之單字組之一。
ex.It’s a disease that affects mainly older people.
(這是一種主要影響老人們的疾病。)
ex.The radiation leak has had a disastrous effect on the environment.
(輻射外洩已經為環境帶來災難性的影響。)
ex.Production was halted until repairs could be effected.
(在修理完成前，生產都停止。)
3. contract/contrast/contrary: contract名詞為「契約」，動詞為「訂契約; 感染」，contrast名詞或動詞語意為「對比」，contrary為名詞或形容詞，語意為「相反(的)」。
ex.He contracted malaria while he was traveling.
(他在旅行時感染了瘧疾。)
ex.Their economy has expanded, while ours, by/in contrast, has declined.
(他們的經濟增長，對比之下，我們的經濟下滑了。)
ex.The crime problem has not disappeared. On the contrary, it seems to be becoming worse again.
(犯罪問題並沒有消失。相反地，似乎又變得更嚴重了。)
4. principle/principal: principle為名詞，語意為「原則」; principal名詞為「校長; 資本，本金」，形容詞為「重要的」。
ex.The organization works on the principle that all members have the same rights.
(該組織的運作原則是所有成員都享有相同的權利。)
ex.The principal aim of this meeting is to reach a decision that we all agree on.
(這場會議的主要目的，就是要做出一個我們都贊同的決定。)
ex.She lives off the interest and tries to keep the principal intact.
(她靠利息過日子，儘量不動用本金。)
5. immigrate/emigrate: 此兩個單字皆為動詞，語意皆為「移民」，但immigrate為「移入」之移民，emigrate為「移出」之移民。
ex.About 6.6 million people immigrated tothe United States in the 1970s.
(1970年代，大約有660萬人移民到美國。)
ex.My grandparents emigrated from Vietnam to the US in the 1980s.
(我的祖父母在1980年代從越南移民到美國。)