Don’t have the clock ______ , Your father is sleeping.
If he ___ me his telephone number yesterday, I ___ able to ring him up now.
The internet has made ____ possible for everyone to talk with friends miles away.
The _________ at the military academy is so rigid that students can hardly bear it.
I remembered _____ the door before I left the office, but forgot to turn off the lights.
Teachers required that all the students ___ their homework all alone.