
"Because" introduces a full clause with subject and verb; "because of" is followed by a noun or pronoun.
"Because" introduces a full clause with subject and verb: it explains the reason with a sentence. "She left because she was tired".
She was late because the traffic was terrible.
He could not sleep because he was too nervous.
I chose this career because I love helping people.
"Because of" introduces a noun or gerund, not a full clause. "She left because of the noise". It cannot be followed by subject + verb.
She was late because of the traffic.
The game was canceled because of the rain.
He could not sleep because of his nerves.
Common mistake
Trick to remember it
Is there a subject + verb after? Use "because". Is there only a noun or pronoun? Use "because of". Formula: because + [subject + verb]. Because of + [noun].
Quick rule
"Because" + clause (subject + verb). "Because of" + noun.
Did you know?
"Due to" and "owing to" are synonyms of "because of": always followed by a noun ("Due to the rain, the game was canceled"). In formal English, "due to" is often preferred over "because of". "Since" and "as" are synonyms of "because" with a clause ("Since it was raining, we stayed inside"), more formal and less emphatic than "because".
Exercise 1 · Pick the right one
The match was cancelled _____ heavy rain.
Exercise 2 · Pick the right one
I was late _____ the traffic was terrible this morning.
Exercise 3 · Form the word
"Despite" is followed by a noun; "although" introduces a full clause with subject and verb.
One is followed by a noun, the other is followed by a full clause.
'A' is used before consonant sounds; 'an' is used before vowel sounds.
'A lot of' works for countable and uncountable; 'many' only for countable; 'much' only for uncountable.
Bryan López
Founder of SpeakUP Academy