A few people have asked me about the difference between “because” and “since”, so that’s what I’ll write about today.
Generally speaking, we use “because” to state the reason for something that the listener or reader doesn’t already know, or when it’s uncertain if they know or not. We use “since” to emphasize the reason for something that is already known to the listener or reader. For example:
I went to Hawaii because I wanted to visit my friend there.
Because my best friend lives in Hawaii, I often go there to visit her.
Since my best friend lives in Hawaii, I often go there to visit her.
You shouldn’t let your children play around here because it’s a dangerous area.
Because this is a dangerous area, you shouldn’t let your children play around here.
Since this is a dangerous area, you shouldn’t let your children play around here.
I’m really nervous because this is my first time to give a presentation at work.
Because this is my first time to give a presentation at work, I’m really nervous.
Since this is my first time to give a presentation at work, I’m really nervous.
So, in the examples above I first used “because” in the middle of the sentence. This indicates that the speaker thinks they are stating a reason that the listener doesn’t know.
After that, I used “because” at the beginning of the sentence. This indicates that the speaker isn’t sure if the listener knows the reason or not.
Finally, I used “since” at the beginning of the sentence. This indicates that the speaker thinks they are stating a reason that the listener already knows.
My statement about using “because” at the beginning of a sentence is not a strict rule but, in my opinion, it’s a good guideline for when to use “because” at the beginning of a sentence.
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