THE COFFEE WAS NOT STRONG, SO IT DIDN’T KEEP US AWAKEA. THE COFFEE...
53. The coffee was not strong, so it didn’t keep us awake
a. The coffee was very strong, but it couldn’t keep us awake.
b. The coffee was so strong that it kept us awake.
c. The coffee was not strong enough to keep us awake.
d. We were kept awake because the coffee was so strong.