The parents felt helpless when they found their son had ____ love stories for long. [ ]

Not until Mary reads her composition the second time ___________the spelling mistake.

are many places in the world have been visited only by a few, many are of enormous beauty.

You can get the best result ________ youcarry out the experiment under the desired conditions

11. It is because people are likely to stayindoors ______ the virus can spread easily ______ people often catch colds.