Gradable & Non-Gradable Adjectives

Adjectives can be either gradable or non-gradable

Gradable

Gradable adjectives are adjectives like ‘cold’ ‘hot’ and ‘frightened’. You can be very cold or a bit cold. Gradable adjectives show that something can have different degrees.

Non-gradable

Non-gradable adjectives are adjectives like ‘married’ or ‘wooden’. You can’t be very married or a bit married. Non-gradable adjectives do not have different degrees.

Adjectives like ‘terrifying’, ‘freezing’ ‘amazing’ are also non-gradable adjectives. They already contain the idea of ‘very’ in their definitions – ‘freezing’ means ‘very cold’ etc.

Using adverbs of degree

When we use adverbs of degree to modify adjectives we usually have to use different adverbs for gradable and non-gradable adjectives.

    NOT I’m completely hot.
    NOT It was very fantastic!

With gradable adjectives

    It’s a bit cold in here. Shall I turn the fire on?
    He’s very interested in history. Why don’t you buy him a history book?
    This exercise is really difficult. I don’t know any of the answers.
    I’m extremely tired. I’m going to bed.

The adverbs a bit, very, really, extremely and quite can all be used with gradable adjectives.

With non-gradable adjectives

    It’s absolutely freezing in here. Shall I turn the fire on?
    He’s completely fascinated by history. Why don’t you buy him a history book?
    This exercise is absolutely impossible.
    That film is really terrifying. Don’t go and see it on your own.

The adverbs absolutely and completely can be used with non-gradable adjectives.

Notice that really can be used with both gradable AND non-gradable adjectives.

NOTE: There are other adverbs of degree that we haven’t covered in this section. The ones included here are some of the most common.

Reference:
1. http://learnenglish.britishcouncil.org/en/quick-grammar/adjectives-gradable-non-gradable#sthash.jcjRxfdb.dpuf