--- It’s a long time ____ I saw you last. --- Yes, and what a pity. It will be a long time ____ we see each other again.
___ smoking here will be fined.
_____ seen smoking here will be fined.
_____ with a good education can apply for the job.
According to the rules, students must not _____ their books during examinations.
She may have missed the train, in _____ case she won't arrive for another hour.