Linkers - Reason and result

I’m so tired SO / BECAUSE I’ve just spent the whole day cleaning the apartment!

Anna goes to bed at around 9 every night, AS A RESULT / SINCE she has to get up early for work in the morning.

It was my birthday yesterday, SO / AS I invited a few friends over to my place.

Jack works in another city most of the time. THEREFORE / SINCE, he can’t see his friends as often as he would like to.

We had a big celebration last night at the office. BECAUSE / AS A RESULT, the office was in a terrible mess this morning.

I’ve got a busy week, SO / AS I need to have a good rest.

AS / THEREFORE I lived abroad a lot when I was a child, I have friends all over the world.