He didn't have much money. He couldn't live on it. (enough)
It's difficult to understand him because he speaks so softly
->He speaks.................................................................
->He doesn't speak....................................................
->He speaks
He í tall, so he could almost touch the ceiling
->He is..............................................
->He is..............................................
He drank strong coffee so that he couldn't go to sleep
->The coffee.....................................................
->He drank..........................................................