When we talk about two things, we can “compare” them. We can see if they are the same or different. Perhaps they are the same in some ways and different in other ways. We can use comparative adjectives to describe the differences.
Comparative adjectives are used to compare differences between the two objects they modify (larger, smaller, faster, higher).We use comparative adjectives when talking about two things (not three or more things).
They are used in sentences where two nouns are compared, in this pattern:
Noun (subject) + verb + comparative adjective + than + noun (object).
The second item of comparison can be omitted if it is clear from the context (final example below).
- My house is larger than hers.
- This box is smaller than the one I lost.
- Your dog runs faster than Jim’s dog.
- The rock flew higher than the roof.
- Jim and Jack are both my friends, but I like Jack better. (“than Jim” is understood)
Formation of Comparative Adjectives
There are two ways to make or to “form” a comparative adjective:
- short adjectives: add “-er”
- long adjectives: use “more”
|Short adjectives: add -er||examples|
|1-syllable adjectives||old, fast|
|2-syllable adjectives ending in -y||happy, easy|
|RULE: add “-er”||old → older|
|Variation: if the adjective ends in -e, just add -r||late → later|
|Variation: if the adjective ends in consonant, vowel, consonant, double the last consonant||big → bigger|
|Variation: if the adjective ends in -y, change the y to i||happy → happier|
|Long adjectives: use more||examples|
|2-syllable adjectives not ending in -y||modern, pleasant|
|all adjectives of 3 or more syllables||expensive, intellectual|
|RULE: use “more”||modern → more modern|
expensive → more expensive
With some 2-syllable adjectives, we can use “-er” OR “more”:
quiet → quieter/more quiet
clever → cleverer/more clever
narrow → narrower/more narrow
simple → simpler/more simple
Exception: The following adjectives have irregular forms:
good → better
well (healthy) → better
bad → worse
far → farther/further
Use of Comparative Adjectives
We use comparative adjectives when talking about 2 things (not 3 or 10 or 1,000,000 things, only 2 things).
Often, the comparative adjective is followed by “than”.
Look at these examples:
- John is 1m80. He is tall. But Chris is 1m85. He is taller than John.
- America is big. But Russia is bigger.
- I want to have a more powerful computer.
- Is French more difficult than English?
If we talk about the two planets Earth and Mars, we can compare them as shown in the table below:
|Diameter (km)||12,760||6,790||Mars is smaller than Earth.|
|Distance from Sun (million km)||150||228||Mars is more distant from the Sun.|
|Length of day (hours)||24||25||A day on Mars is slightly longer than a day on Earth.|
|Moons||1||2||Mars has more moons than Earth.|
|Surface temperature (degrees Celcius)||22||-23||Mars is colder than Earth.|
Although we use comparative adjectives when talking about two things (not three or more things), in fact one or both of the things may be a group of things.
- Mt Everest is higher than all other mountains.
Here, we are talking about hundreds of mountains, but we are still comparing one thing (Mt Everest) to one other thing (all other mountains).