2. I couldn't read my book because it was dark.
3.She couldn't swim because the water was very cold.
4.We couldn't eat out dinner because we weren't hungry.
5.I couldn't speak to Kevin because ha wasn't home.
6.They couldn't play tennis because it was wet.
7.I couldn't sleep because I wasn't tired .
8.They couldn't buy alcohol because they weren't 18 years old.
Bardzo proszę ;P