MODAL AUXILIARIES

On the average, a healthy heart _________ to pump five tablespoons of blood with every beat.

• must

• ought

• can

• should

Civil engineers had better ___________ steel supports in concrete structures built on unstable geophysical sites.

• include

• including

• inclusion

• included

Would you please _____________ the listening comprehension script until after you have listened to the tape?

• not to read

• not read

• don’t read

• don’t to read

The cones of pine trees ___________ two or three years to reach maturity.

• to take

• taking

• may take

• takes

Even without strong wings, the ostrich has survived because it ___________ at high speeds to escape predators.

• to run

• can run

• running

• run