This morning in the class, our teacher lost his ______at last because he could not stand any more.

Several loudspeakers are _______ from the ceiling and we can hear the speaker very clearly.

We do not have a _______ school in our institute. The highest degree we provide for the students is a B. A. and a B.S. .

The engineers in this lab spent several weeks _______their plans for the new bicycle.

The _______ work continued for more than a week but there was still no sign of the missing boy.