what is the difference between "like" and "as"?
Do people use these in similar situations?
Like and as are used with a comparable meaning in two situations.
When I compare two things that are equal in some way, I use as...as...
My brother is as tall as my father.
John is as rich as Paul.
This means that my brother and my father have the same height, and that Paul and John have the same amount of money.
When I compare two things that are similar in some way, I use like.
My brother is tall, like my father.
John is rich like Paul.
This means that both my father and my brother are tall, taller than average, but they are not necessarily the same height. Also, John and Paul both have more money than most people, but one can still have more than the other.
In these sentences, I just express that they both share a property (being tall, or being rich), but they do not have to have the property to the same extent.
If I do something in a way similar to the way someone else would do it, or if I describe that something has a property in a similar way some other object does, I use like.
He handled the situation like a gentleman.
This vehicle has four wheels, like most cars.
I am not saying that he actually is (always) a gentlemen, but the way he handled this situation was the way a gentleman would handle it, so his behaviour was similar to that of gentleman.
This vehicle may not be an actual car, but it is like a car in the sense that it has four wheels.
Now, if I do something because I am a certain kind of person, or I describe that something has a certain property because it is a certain kind of abject, I use as.
As a gentleman, he handled the situation very well.
As a car, this vehicle has to have four wheels.
Because he is a gentleman, he handled the situation well; since the vehicle is a car, I expect it to have four wheels.
You can use being to replace as in these sentences to convey the same meaning:
Being a gentleman, he handled the situation very well.
Being a car, this vehicle has to have four wheels.