Students ________ to do some voluntary work every year.

voice

non-gradable adjectives

modal auxiliary

anaphoric reference

Explain the difference between a double relative clause and an embedded relative clause.

Using the passive voice:

A group of children built the sand castle.

List two situations in which the simple present is used to refer to the past.

Using an adjunct:

He ran away. He is afraid to be seen.

Using extraposition:

That he should refuse to help made her very disappointed.

Using a modal auxiliary:

The Bulls were probably not well prepared for the third game of the 1997 NBA final.