I couldn't believe my eyes because ...
I was worried because ...
Yesterday I was disapponted because ...
I couldn't understand the foreigner because ...
I couldn't wait to see my friend agai because ...
I couldn't fall asleep because ...
I failed the test because ...
I didn't want to call mom because ...
I suddenly remembered that ...
I didn't want to go to the cinema because ...
I wasn't hungry in the morning because ...
I couldn't find my charger because ...
I couldn't attend my English class bacause ...
Last weekend I was really tired because ...