Because\As\Since的用法

Because, as, since

Reasons
Because, as?and?since?are all used to give reasons.

I'm tired because I didn't sleep well.

I'm tired as I didn't sleep well.

I'm tired since I didn't sleep well.
Because

Because?focuses on the reason for something.It is more common than?as?or?since.

We can put the?because clause?at the beginning of the sentence. When we do so, we need to add a comma between the two clauses.

You're reading this because you want to learn English.

They won't be here because they're on holiday.

Because you want to learn English, you're reading this.

Because they're on holiday, they won't be here.

As and since

As?and?since?focus on the result of something rather than the reason for it.

We can put the?as?or?since?clause?at the?beginning of the sentence. When we do so, we need to add a comma between the two clauses.

I hope Tom's brought that comic as I wanted to borrow it from him.

Noodles are popular since they're easy to cook.

As I wanted to borrow that comic, I hope Tom's brought it with him.

Since they're easy to cook, noodles are popular.

Hi! I'm Tim from BBC Learning English and today I'm going to tell you about three useful words:?because,?as?and?since.

These are all used to give reasons.

Because?is more common than?as?or?since?and we use it when we want to focus on the reason.

I'm tired?because I didn't sleep very well.

When we want to give extra focus to the reason, we can put the?because?clause at the beginning of the sentence.

Because my bed is uncomfortable, I'm getting a bad back.

As?and?since?are more formal than?because?and we use them to focus on the result rather than the reason.

I hope Tom's brought that comic?as I wanted to borrow it from him.

Noodles are popular?since they're easy to cook.

We often use?as?and?since?clauses at the beginning of the sentence. Just remember to add a comma.

So,?as our minute is up, I'll finish recording this video.