For instance "get" mean to come to have something, but when it is follow by "up" being "get up" mean to wake up and get out of bed.

With that having been explained is why it is said that "Phrasal verbs are a crucial part of English. They give the language depth and nuance." – Michael Swan.

Different reasons would be that:

° They are common in everyday speech and conversations.

° They convey specific meanings that are not immediately obvious from the individual words.

° They help you express ideas more clearly.

° They can make your English sound more informal and friendly.

° They help you understand and use idiomatic expressions.

° Look up to: means to respect and to admire someone, which is an inspiration in life.

E.g.

Her younger siblings look up to her, especially Stephanie.

° Look ahead: means to think about and plan for what might happen in the future.

E.g.

It is much better to look ahead and plan daily or even weekly meals.

° Look forward to: means to be pleased or excited that it is going to happen.

E.g.

I look forward to it.

° Look for: it to attempt to find someone or something.

E.g.

I think I'm ready to look for that car now.

° Look after: means to take care of or be in charge of someone or something, is used to make sure that someone or something is safe and well.

E.g.

You don't have to look after me, you know.

° Get away: means to leave or escape from a person or place, often when it is difficult to do this.

E.g.

Once you get away from him, stay away.

° Get along: is to have a good relationship or deal successfully with a situation.

E.g.

Friendship is forever and everyone should try to get along.

° Get down to: is to start to do something.

E.g.

So how did he get down to the point where he fell?

° Get by: means to manage to live or do a particular thing using the money, knowledge, equipment, etc.

E.g.

Few households can get by without a set of dinnerware.

° Get over: is to accept an unpleasant fact or situation after dealing with it for a while. IT can also mean to recover from something, such as when you have been sick or emotionally upset, and you are now feeling better.

E.g.

Maybe they had time to get over the shock.

° Take over: is to get control of something, or to do something instead of someone else, to be in possession of something.

E.g.

Tears burned her eyes, but she refused to let emotion take over again.

° Take back: it can mean from return something you have bought to a shop to admit that something you said was wrong.

E.g.

You could at least take back your words.

° Take after: means to be like or to look like another family member or part of the family.

E.g.

Mark is so hot-headed. He takes after his father.

° Take up: is to fill or use an amount of space or time, also to learn or start to do something, especially for pleasure.

E.g.

He can't wait to take up the sport.

° Take in: means to view your surroundings and absorb them, such as scenery or surroundings or to understand completely the meaning or importance of something.

E.g.

He found himself stretching his head back to take in the view.

° Give back: is to provide help or financial assistance to others in appreciation of one's own success or good fortune on the other hand, is to return something to its owner.

E.g.

Encourage your child to give back to his community.

° Give out: means to make a piece of information public, especially information that is not true, to allow to be known; declare publicly and even to distribute.

E.g.

You should never give out your passwords.

° Give off: in simple words is to produce something such as a smell, heat, light, etc.

E.g.

These jeans don't give off that same cool to the touch feeling.

° Give up: to stop doing something, especially something that you do regularly.

E.g.

It was too soon to give up hope.

° Give in to: means to finally agree to something that someone wants after first refusing.

E.g.

She refused to give in to the nagging question of brain damage.

Phrasal verbs definicion and ways of use.

I can also conclude that they are versatile, depending on their context, since their meaning changes depending on the word or words that follow it, therefore this flexibility makes them powerful as well as turning them into a tool of expression that using them as verbs alone would not give it the context or that expressiveness that we need to say.

And finally I can say that the use of these is more than anything cultural, since they reflect more than anything the nuance that can exist within a culture or region with different expressions that are not necessarily going to have the same meaning, depending on the area in which we find ourselves.