The Great Vowel Shift played a significant role in the history of English.

He worked hard to accomplish his goals.

His role is the team leader.

This graph shows the transition of the economy.

The climate of this region changes according to the season.

Health is very important.

His opinion is very important.

He is interested in history.

I achieved a big success.

In this old document, the usage of vowels is different from today.