"because of"

I couldn't go there because of a headache.
I couldn't concentrate because of a headache.

I felt depressed because of the weather.
I felt to get down my motivation because I don't like my company thinking.

I couldn't sleep well owing to mosquitoes.
I got wet owing to rain.

I couldn't attend the party on account of previous appointment.

I was able to pass the exam thanks to my teachers.
My headache is getting better thanks to massage of my husband.

We couldn't go on a picnic because it rained.
We couldn't eat much because we ate lunch a lot.

Since I was in such a hurry, I forgot to bring my cell phone.
Since I didn't ask anything, we have misunderstanding.

As I studied till late last night, I couldn't get up early this morning.
As I was very busy I couldn't clean our room.

Now that I have finished my diary, I can go to bed.
Now that I had a payday, I can withdraw some money.

I must have a cold, for I cough.
It must be snow, for it's so cold.