With so many different forms of poetry ______, students may eventually want to write poems of their own.

The possibility __________ pleasant smells might reduce pain has recently been suggested by new research.

With a report _____ about the accident, the policeman has to find some witnesses for help.

The answer ________ the teacher,she asked the little boy to try a second time．

It was a pity that the great writer died _______his works unfinished.