The attacks occurred throughout the 20th century, but the periods of greatest activity were during the 1920s and 1960s.

His years of greatest activity were from 1671 to 1716.

But, perplexingly, the greatest activity seemed to center around a large open hatch in the middle of the deck.

Baxter's health had grown even worse, yet this was the period of his greatest activity as a writer.

O'Klein's period of greatest activity as an artist was during the 1930s, 1940s, and 1950s.

The greatest activity occurs three hours before sunrise and after sunset.

The warm months see the greatest activity, but it is really a year-round phenomenon.

The greatest activity in the world is to sit outside a cafe and watch the world go by.

The greatest activity by hedge funds has been in the credit business.

This was his period of greatest activity, and he received numerous important commissions.