Cause
Why does something happen or turn out this way?
المعنى
A cause explains why something happens or why a situation is as it is. It may be an earlier event, a circumstance, or someone's reason for acting. Languages use linking words, endings, or context, and some have no separate cause marker. Unlike Purpose, Cause explains what brings about an event, not what someone hopes to achieve.
طريقة التعرّف عليه
Find the part that answers why the event happened or why the situation is as described.
في اللغة الأم
Arabic introduces a reason stated as a sentence with لأنّ, followed by a noun subject or an attached subject pronoun. بسببِ introduces a cause expressed as a noun or noun group. These expressions explain what brought about a situation, not what someone hopes to achieve.
عدتُ إلى البيتِ لأنني نسيتُ المفاتيحَ. (ʿUdtu ilā al-bayti li-annanī nasītu al-mafātīḥ.)
The attached ـني supplies the subject of the reason clause.
تأخرتِ الحافلةُ بسببِ المطرِ. (Taʾakhkharati al-ḥāfilatu bi-sababi al-maṭar.)
بسببِ introduces a noun naming the cause.
في اللغة قيد التعلم
English uses because to introduce a reason expressed as a full clause, a part with its own subject and verb. Because of comes before a noun or a noun phrase, a group of words built around a noun. Since and as can also introduce reasons, though they have other meanings in other contexts.
I took a taxi because I was late.
Because introduces a reason with its own subject and verb.
The game was canceled because of the rain.
Because of is followed by a noun phrase, not a full clause.
Since the store is closed, we'll come back tomorrow.
Since gives a reason here; it does not mark a starting time.
Learners whose language uses one expression before both nouns and full clauses may confuse because and because of. Learners whose language regularly pairs cause and result markers may use because and so together in a sentence where English normally uses just one.