Source: Swan. M. 2005. Practical English Usage Oxford, United Kingdom: Oxford University Press (2011).
Practical English Usage lists over a hundred common mistakes in the English language. Even advanced students of English make mistakes. Swan (2005) has listed a number of them.
“I’ll ask you in case I need help.” = I’ll ask you if I need help.
(271.3) In case and if are normally used in quite different ways. ‘Do A in case B happens’ means ‘Do A (first) because B might happen later’. ‘Do A if B happens’ means ‘Do A if B has already happened’.
“I object to tell them my age.” = I object to telling them my age.
(298.2) To is actually two different words. It can be an infinitive marker, used to show that the next word is an infinitive (e.g. to swim, to laugh). It can also be a preposition, followed for example by a noun (e.g. She’s gone to the park, I look forward to Christmas). (298.1) When we put a verb after preposition, we normally use an -ing form (‘gerund’), not an infinitive.
“I like the 60s music.” = I like the music of the 60s. / … 60s music.
(69.3) Some expressions are ‘half-general’- in the middle between general and particular.
“ten thousand, a hundred and six.” = ten thousand, one hundred and six.
(389.11) We can say an eighth or one eighth, a hundred or one hundred, a thousand or one thousand, a million or one million, etc. One is more formal. A can only be used at the beginning of a number.
“‘Who’s that?’ – ‘He’s John.'” = ‘Who’s that?’ – ‘It’s John.’
(428.9) We use it for a person when we are identifying him or her.
“I don’t like to be shouted.” = I don’t like to be shouted at.
(416.1/80.3) The objects of prepositional verbs can become subjects in passive structures. We have looked at the plan carefully. – The plan has been carefully looked at. Note the word order. The preposition cannot be dropped.
“It’s ages since she’s arrived.” = It’s ages since she arrived.
(522.2) In British English, present and past tenses are common in the structure It is / was … since …
“The police is looking for him.” = The police are looking for him.
(524.7) Cattle is a plural word used to talk collectively about bulls, cows and calves; it has no singular, and cannot be used for counting individual animals. Police, staff and crew are generally used in the same way.
See other: Notes On English Grammar