Better sooner than later: More on comparatives: How and When to Use in English

My mother is older than my sister. When you compare two elements, put than before the second element of the comparison, in this case my sister. Example: the US is bigger than the UK.

Of can be used to show possession, but not to compare two elements. Example: he is a good friend of mine.

We don't use with to compare elements. Example: I am at the beach with my family.

Susan's car is better than mine. Better is the irregular comparative form of good. Examples: my football team is better than yours; we need to come up with a better solution.

Use good simply to describe something. However, here we want to compare two elements (as shown by than). Example: the meal was good.

Betty, Betty, Betty… she is everywhere! However, she shouldn't be in this sentence!

The hotel room is more expensive than before. When using a long adjective in a comparison, follow the structure: more + adjective (here, expensive) + than. Example: going to the spa is more relaxing than jogging.

Plus is the symbol “+”, but we don't use this word in a comparison. Example: two plus two makes four.

You can say the hotel room is very expensive, but you can't use very to compare two things. 

Health is more important than money. Use the structure more + long adjective (here, important) + than to compare two things. Example: driving is more dangerous than walking.

The film is longer than the show. When you compare two elements using a short adjective like long, follow the structure: long + -er + than. Example: my father is stronger than my brother.

Roger's bag is more expensive than Magda's. Since expensive is a long adjective, use more before the adjective (expensive) and than to introduce the element you want to compare with (here, Magda's bag). Example: this chair is more comfortable than that one.