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 very advanced students of English can make mistakes – nobody’s perfect! Swan (2005) has listed a number of them.
“The number of the unemployed is going up.” = The number of unemployed is going up.
(70.7) The is dropped about the amount/number of.
“She was showing tiredness signs.” = She was showing signs of tiredness.
(384) Many nouns, especially abstract nouns, can be followed by ‘compliments’ – other words and expressions that ‘complete’ their meaning. These complements can be prepositional phrases, infinite expressions or clauses (with or without expressions).
“She works the hardest when she’s working for her family.” = She works hardest when she’s working for her family.
(141.6) The cannot be dropped when a superlative is used when we compare the same person or thing in different situations. However, we do not use the with superlatives when we compare the same person or thing in different situations.
“I’m thankful for your help.” = I’m grateful for your help.
(582) Grateful is the normal word people’s reactions to kindness, favours etc. Thankful is used especially for feelings of relief at having avoided a danger, or at having come through an unpleasant experience.
“We talked about if it was ready.” = We talked about whether it was ready.
(453.4/621.2) If does not normally follow prepositions; we use whether instead.
See other: Notes On English Grammar