comparative adjectives：
比较级：

We use comparative adjectives to describe people and things:
我们用比较级形容词来描述人或物：

This car is certainly better but it’s much more expensive.

I’m feeling happier now.

We need a bigger garden

We use than when we want to compare one thing with another:
当我们想要比较两种物体时，我们用than：

She is two years older than me.

New York is much bigger than Boston.

He is a better player than Ronaldo.

France is a bigger country than Britain.

When we want to describe how something or someone changes we can use two comparatives with and:
当我们想要描述某物或某人的改变时，我们可以用两个比较级来描述：

The balloon got bigger and bigger.

Everything is getting more and more expensive.

Grandfather is looking older and older.

We often use the with comparative adjectives to show that one thing depends on another:
我们经常用the和比较级形容词一起来表现某物依赖于某物：

When you drive faster it is more dangerous

> The faster you drive, the more dangerous it is.

When they climbed higher it got colder
> The higher they climbed, the colder it got.

Superlative adjectives:
最高级

We use the with a superlative:
我们用the与最高级连用：

It was the happiest day of my life.

Everest is the highest mountain in the world.

That’s the best film I have seen this year.

I have three sisters, Jan is the oldest and Angela is the youngest .