27.After the bell rings, which indicates the ending of the exam, you ______stay where you are until all your papers are collected.
___________ is known to everybody, the noon travels around the earth once every month.
A computer can only do ________ you have instructed it to do.
—If he ___________, he ________that food. —Luckily he was sent to the hospital immediately.
When a pencil is partly in a glass of water, it looks as if it _______.
One learns a language by making mistakes and _______ them.