You use comparative adjectives to compare two things.
A train is bigger than a car.
I am comparing the size of two things, a train and a car. This example uses the comparative form of the adjective 'big'.
You always use 'than' after a comparative adjective when you compare two things.
A train moves faster than a car.
I am comparing the speed of a train and a car. Notice 'than' after the comparative adjective 'faster'.
If you are comparing one thing to many others, you might want to use a superlative adjective.
Spelling Rules For Comparatives
Most comparative adjectives end in -er. The spelling rules are based how many syllables the adjective has.
One Syllable Words
For most one syllable adjectives you make the comparative form by adding -er.
If the adjective already ends in e, you just add -r.
For some adjectives you need to double the last letter before you add -er. You do this when the last three letters of the word have the pattern consonant-vowel-consonant.
Vowels are the letters a, e, i, o, u. All other letters are consonants.
Words Ending in y
For adjectives ending in y, you make the comparative form by changing the y to an i, then adding -er.
Two Syllable Words
For most words with two syllables or more, you make the comparative form by adding the word more before the adjective.
Butterflies are more beautiful than caterpillars.
The adjective beautiful has three syllables. Notice that we use 'more' before 'beautiful' and 'than' after.
Making Comparative Sentences
+ John is taller than Kate. noun=John + v=be + comparative + than + noun=Kate
- John is not taller than Kate. noun=John + v=be + not + comparative + than + noun=Kate
? Is John taller than Kate? be + noun=John + comparative + than + noun=Kate?
? Does John run faster than Kate? Do + noun=John + v + comparative + than + noun=Kate?