c
1、can, be able to
這兩個詞都可以表示“能夠”。can通常用來表示現在的一般能力。如：look, i can do it.嗨，我會做這事啦。而當表示將來能力時，一般要用will be able to。此外，be able to 還表示要經過一番努力才能做到的事。如：if i concentrate on the work, i'll be able to work out the problem.如果我集中思想於工作的話，我就可以想出這個問題的解決方法。i'll be able to speak french in another few months.再過幾個月我就可以說法語了。
2、call on, visit
call on：“拜訪”，為社交用語，強調較正式的訪問。如：i hope to call on you at your office at three o'clock today.我希望今天下午三點鐘到辦公室去拜訪你。
visit：“訪問，參觀”，指為一定目的去訪問某人或參觀某地。如：professor li is often visited by his students.學生們常去看望李教授。
注意：call at與call on都可以作“訪問”解，但call at後接地點；call on後接人。如：i called at the bank and drew some money today.今天我去銀行取了些錢。
3、centre, middle
centre“中心”，指圓和球體的中心點並可用作比喻，指事物或活動中心。如；he placed the flowers in the centre of the table.他把花放在桌子的中央。at the centre of the park there is a monument in memory of the hero.在公園的中央有一個英雄紀念碑。london is the political, economical and cultural centre of britain.倫敦是英國政治，經濟和文化中心。
middle：“中間”，指空間或時間意義上與兩端等距離的中間部分。如：he telephoned me in the middle of the night.他半夜給我打來電話。soon they were in the middle of the river.不久他們來到河中央。
4、chance, opportunity
chance表示“機會；可能性（強調偶然性）”，如：if we can swim, the chances are that we can save our lives.如果我們會游泳的話，我們就有可能得救。harold has lost a lot of money so he wants to take a chance on stock exchange.海洛得丟了很多錢，因此他想在股票上碰一碰運氣。
而opportunity表示機遇（強調好時機），既可作可數名詞又可作不可數名詞。如：this has been my only opportunity to practise speaking english.這一直是我練習英語口語的唯一機會。i am very glad to have had the opportunity to talk to you.我很高興能有機會與你交談。
5、certain, sure
certain表示“有把握的，確信的”，語氣較強，主語可以是人也可以是物，表示有充分的信心。有時也有“某些”的含義。如：it is certain that the temperature will rise.氣溫一定會上升。he is certain to come.他一定會來。
sure“確信的，無疑的”，作此義解時，主語常為人而不是物。如：he is sure to succeed.他一定會成功。注意：certain和sure在接不定式和of短語時意思上有差別。試比較：they are certain/sure to succeed.他們一定會成功。they are certain/sure of success.他們有成功的把握。第一例用不定式表示說話人對某事的推斷，有“一定，必然”的含義；第二例用of短語表示主語本人的信念，有“確信，對...有把握”的含義。再如：the strike is certain/sure to take place.罷工必然會發生。they are certain/sure of victory.他們確信會獲得勝利。
6、care about, care for
這是兩個動介型短語動詞，後接名詞或代詞作其賓語。在表示“為...擔憂”的意思時，兩者可交換使用。
care about主要用來表示“對...感興趣；關心；在乎”的意思。如：i don't much care about going.我並不很想去。i don't care about what people think.我不在乎人們怎么認為。
care for則主要用來表示“喜歡，對...中意”和“照顧”等意思。如：she doesn't seem to care for him.她好像不喜歡他。small children are well cared for in nurseries when their parents are working.當父母在工作時，孩子們在託兒所里受到良好的照顧。
7、carry on, carry out
carry on意為“進行，繼續”，強調一個行為的進行過程。它可以不跟賓語，也可接表示“工作，討論，競賽，戰鬥”等一類的名詞作賓語，相當於continue。它另可作“經營”解，相當於manage。如：don't let me interrupt you, just carry on.別讓我打斷你，請繼續。i'll try to carry on the work in spite of difficulties.儘管有困難，但我還是會繼續這項工作。rising costs make it hard to carry on the business.成本上升給生意經營帶來了困難。
carry out意為“進行，貫徹，實現”，含有按照某個要求或準則進行的意思。它必須接賓語，且賓語往往是表示“工作，活動，職責，命令，計畫”等一類的名詞。此詞語相當於put into practice。如：i have some difficulties in carrying out her order.我感到執行她的命令有些困難。the government was trying to carry out the policy of "family planning".當時，政府正盡力貫徹“計畫生育”政策。
8、catch up with, keep up with
catch up with為“趕上（某人或某事）”，有追上並可能超過的含義。如：we'll do out best to catch up with the advanced industrial countries.我們將盡力趕超先進的工業國家。
keep up with作“不落後於（某人或某對手）”解，有與之並駕齊驅的含義。如：the girls had to run to keep up with the boys.這些女孩子不得不加快腳步以趕上男孩子們。
9、cause, reason
10、clothes, clothing, cloth
11、chief, main
12、choose, select
13、come to one's help, come for one's help
14、continual, continuous
15、compare...to, compare...with
16、consider, regard as, treat as
17、coloured, colourful