Using Facts and Speculations

Rewrite each sentence using must/may and the correct form of the verb. Use must when the statement is likely to be true and may when the statement is possibly true.

1		It took many years to construct the pyramids at Giza.
2		Some archeologists believe that slaves were used to build the pyramids.
3		Much of the treasure in the pyramids was taken by grave robbers.
4		Perhaps an epidemic caused the abandonment of the great Mayan cities.
5		There is some evidence that mummification took place in the temple.