We looked everywhere for the keys, but they are nowhere _______.

If ____ unsolved, the problem of food safety may lead to more serious results.

 Many activities in the shop, _______ many different types of interest, are planned _______ its out-of-date goods.

When I got back home, I saw a message pinned to the door     “ Sorry to miss you, I will call later.”

After the National Entrance Examination the students will have an anxious couple of weeks _____ for the results.