Use because + a clause and because of + a noun phrase to give a reason.
Because vs. because of
Not ""The event was canceled because the storm." (no verb after because)" — say ""The event was canceled because of the storm."". A bare noun needs because of; a full clause with a verb needs because.
Try it: Mei: Why did Yasmin miss the call? Lani: She missed it ___ a problem with her phone. Choose the words for the blank. (because of / because / because that) Answer: because of — Because of comes before a noun phrase like a problem with her phone.
Word
Pronunciation
Example
because
Maya was late because the bus was delayed.
because of
Sofia was late because of heavy traffic near Ghafwick Station.
Since (known reason) and due to (formal)
Use since for a reason the listener already knows; use due to, a formal because of, before a noun phrase.
Not ""The train was delayed due to it snowed." (clause after due to)" — say ""The train was delayed due to signal problems."". Due to takes a noun phrase, just like because of, never a full clause.
Try it: Wei: Why did the clinic close early? Farid: The notice says it closed ___ staff training. Choose the words for the blank. (due to / since / because) Answer: due to — Before a noun phrase in a formal notice, use due to.
Word
Pronunciation
Example
since
Since Amina has the keys, she can open the office.
due to
The outdoor class was moved inside due to bad weather.
The reason why
Use the reason why + a clause to make the cause the focus of your sentence.
Try it: Ethan: Why did you two leave the party so early? Mei: ___ we left early was the music. It was far too loud. Choose the words for the blank. (The reason why / The reason why of / The reason why because) Answer: The reason why — The reason why is followed directly by a clause, with no of or because.
Word
Pronunciation
Example
the reason why
The reason why Farid left early was that he had an appointment.
explain the reason why
Amina explained the reason why the deadline was extended.
as and thanks to
Use as + a clause the way you use since, and thanks to + a noun phrase for a reason that brought something good.
Try it: Lani: How did your team win the quiz? Wei: ___ Amina. She knew every science answer. Choose the words for the blank. (Thanks to / Because / As) Answer: Thanks to — Thanks to + a noun gives the reason for something good; because and as need a clause.
Word
Pronunciation
Example
as
/æz/
As it was late, we took a taxi home.
thanks to
/θæŋks tuː/
We finished early thanks to Wei's help.
What are the common mistakes?
Incorrect
Correct
Why
"The event was canceled because the storm." (no verb after because)
"The event was canceled because of the storm."
A bare noun needs because of; a full clause with a verb needs because.
"The train was delayed due to it snowed." (clause after due to)
"The train was delayed due to signal problems."
Due to takes a noun phrase, just like because of, never a full clause.