Four common mistakes at IELTS Advanced

1. the before general concepts

        We use the before nouns which describe a general type of thing rather than a specific example of that thing.

        The is also used before abstract nouns which describe a situation, a quality, a process or a change. These words are often followed by of something.

        We use the development/improvement, etc. of something to describe a general process of change, but developments/improvements, etc. in something to describe specific changes.

2. a/an before noun phrases 

        Don’t forget to include a/an before an adjective + singular noun combination.

        Notice the position of adverbs (very, really, quite, etc.) in these phrases.

        Some common noun phrases to be careful with:

• to a certain extent/degree: I agree with you to a certain degree.

• a wide range/variety: We have a wide range of books to choose from.

• a(n) large/small/equal number/amount: an equal number of men and women

• a high/large/small/greater proportion/percentage: a small proportion of patients

• a long time: I haven’t seen her for a long time.

3.  When do I use the capital letters?

        Capital letters are always used for nouns in the following groups:

• countries

• towns, cities, states and regions

• nationalities, ethnic groups and religions – referring to people, languages or things from a country, region or culture

• months and days of the week

        Capital letters are not used for the seasons: spring, summer, autumn, winter

• names of organisations and institutions

        Where a word like museum, university, station or hospital is part of the name of an institution, it has a capital letter. However, when these words are not part of a name, they do not have a capital letter

    Also remember: the Earth (but not the World), the Third World/a Third World country, AIDS, CD/DVD (plural CDs/DVDs).

4. When do I use when, if, whether ?

        We use when to talk about an event or situation that we believe will happen.

        We use if to talk about a hypothetical possibility, especially in conditional sentences.

        We also use if in certain polite requests.

I would appreciate it if / would be grateful if you could call me back.

Would you mind if I asked you a few questions about the accident?

         We use whether where we are considering two possibilities.

        We use whether after certain verbs (and nouns) which involve considering two options.

-----from a excerpt of  "Common Mistakes at IELTS Advanced: And how to Avoid them", 

Julie Moore, Cambridge University Press.