Nouns from verbs

1. Word families.

Which words can you use to complete the four sentences below?

A. The asteroid impact will ___________ a nuclear winter effect.
B. Thousands of asteroids ____________ our planet every year.
C. Scientists are trying to__________ the probability of XF11 hitting the Earth.
D. NASA were quick to __________ the IAU's findings.

2. Word building.

Write the noun form of the verb in bold in the gap.

For example:

NASA said that the IAU's announcement highlighted the need to discuss how the discovery of near-Earth objects is announced.

3. Word building.

Write the noun form of these verbs.

4. Word building.

Complete the sentences by writing the noun or verb form of the words from the previous exercise. Be careful to use the correct form of the verbs.