Lesson 25 Mengapa? (Why?)

You would have noticed that the short answers in Malay do not require the pronoun as it is understood.
While in English the short answers would be: Because I was sick, Because it rained, Because I have lost my passport  in Malay you need only say: Because sick, Because rain, Because lost my passport.
Putting the above answers in a full sentence would produce the following:
Saya tidak datang kerana sakit.
Saya datang lambat kerana hujan.
Saya sedih kerana sudah hilang pasport saya.
Another word that is used as much as kerana is sebab.
Thus to the question Mengapa datang lambat? the answer could just as well be Sebab hujan.
Okay, if mengapa means "why", what does tidak mengapa mean? It is just an expression that means "It doesn't matter", "It's all right" or "Forget about it". It's the same as tidak apa.