A. Study this example situation:
Shirley, Henry and Arthur are all millionaires. They are all very rich.
Shirley has 10 million pounds, Henry has 8 million pounds and Arthur has 2 million pounds. So:
Henry is rich.
He is richer than Arthur.
But he isn't as rich as Shirley. (= Shirley is richer than he is)
Some more examples of not as... (as):
* Tom isn't as old as he looks. (= he looks older than he is)
* The city centre wasn't as crowded this morning as it usually is. (= it is usually more crowded)
* jenny didn't do as well in the exam as she had hoped. (= she had hoped to do better)
* 'The weather is better today, isn't it?' 'Yes, it's not as cold.' (= yesterday was colder)
* I don't know as many people as you do. (= you know more people)
You can also say 'not so. (as)':
* It's not warm but it isn't so cold as yesterday. (=... it isn't as cold as...)
Less... (than) is similar to not as... (as):
* I spent less money than you. (= I didn't spend as much money...)
* The city centre was less crowded than usual. (= it wasn't as crowded...)
B. You can use as... as (but not 'so... as') in positive sentences and in questions:
* 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 like.
* Let's walk. It's just as quick as taking the bus.
* Can you send me the money as soon as possible, please?
Also: twice as... as, three times as... as etc.:
* Petrol is twice as expensive as it was a few years ago.
* Their house is about three times as big as ours.
C. We say the same as (not 'the same like'):
* Ann's salary is the same as mine. or Ann gets the same salary as me.
* Tom is the same age as George.
* 'What would you like to drink?' 'I'll have the same as you.'
D. Than me/than I am etc.
We usually say:
* You are taller than me. (not 'than I')
* He is not as clever as her. (not 'as she')
After than/as it is more usual to say me/him/her/them/us when there is no verb. Compare:
* You are taller than I am. but You are taller than me.
* They have more money than we have. but They have more money than us.
* I can't run as fast as he can. but I can't run as fast as him.