It is considered unwise to give a child _______ he or she wants. 

.A computer is so useful a machine ________ we can use everywhere.

      had never occurred to him that he might be falling in love with the new school.

It was seven o;clock in the morning ____ he came back.It was really at seven o’clock ___ he came back from work this morning.

The man in black was about to set fire to the house ____ the police came.