Study this example situation:

Sarah, Joe and David are all very rich.
Sarah has $20 million, Joe has $15 million
and David has $10 million. So:

Joe is rich.

He is richer than David.

But he isn't as rich as Sarah. (= Sarah is richer than he is)

• Jack isn't as old as he looks. (= he looks older than he is)
• The town centre wasn't as crowded as usual. (= it is usually more crowded)
• Lisa didn't do as well in the exam as she had hoped. (= she had hoped to do better)
• The weather is better today. It's not as cold. (= yesterday was colder than today)
• I don't know as many people as you do. (= you know more people than me)
• 'How much did it cost? Fifty pounds?'  'No, not as much as that.' (= less than fifty pounds)

• It's not warm, but it isn't so cold as yesterday. ( = it isn't as cold as ... )

• I spent less money than you. (= I didn't spend as much money as you)
• The city centre was less crowded than usual. (= it wasn't as crowded as usual)
• I play tennis less than I used to. (= I don't play as much as I used to)

• I'm sorry I'm late. I got here as fast as I could.
• There's plenty of food. You can have as much as you want.
• Let's walk. It's just as quick as taking the bus.
• Can you send me the information as soon as possible, please?

• Petrol is twice as expensive as it was a few years ago.
• Their house is about three times as big as ours.

• Laura's salary is the same as mine. or Laura gets the same salary as me.
• David is the same age as James.
• Sarah hasn't changed. She still looks the same as she did ten years ago.

Than me / than I am etc.

• You're taller than me. (not usually You're taller than I) or You're taller than I am.
• He's not as clever as her. or He's not as clever as she is.
• They have more money than us. or They have more money than we have.
• I can't run as fast as him. or I can't run as fast as he can.