11 He is very ill. He can't eat anything. Therefore, he is unable to consume any food due to his illness.

It won't get through those gates. This means that whatever "it" is, it is unable to pass through the gates.

13 The floor wasn't strong. We couldn't dance on it. The floor lacked strength, so we were unable to dance on it.

14 I was terrified. I couldn't move. Due to my fear, I was unable to move.

15 The bull isn't big. He couldn't harm you. Since the bull is not large in size, it is unable to cause harm to you.

16 The coffee isn't strong. It won't keep us awake. The coffee lacks strength, so it will not be able to keep us awake.

17 The river is deep. We can't wade it. The river has significant depth, so we are unable to wade through it.

18 He is lazy. He won't get up early. Because he is lazy, he refuses to wake up early.

19 He won't get up early so he never catches the fast train. Since he refuses to wake up early, he is never able to catch the fast train.

20 The package is very thick. I can't push it through the letterbox. The package has a substantial thickness, making it impossible for me to push it through the letterbox.