First, the wild animals fled, then the firefighters arrived.

When the firefighters arrived, the animals (a)   . (flee)

We are debating environmental issues in class this whole week.

We (a)   environmental issues in class for the whole week. (debate)

The polar bear swam to safety and then the rescue team arrived.

By the time the rescue team _______, _______ to safety. (arrive / swim)

(a)  

The forest looked grim and bleak. It burnt the entire day.

The forest had (a)   .

They finished their project on climate change today. (use just)

They (a)   .

There is no solution for waste disposal according to scientists. (use yet)

The scientists (a)   . (find)

Mari wrote her essay after searching for information about water shortage.

Mari (a)   for information about water shortage before she wrote her essay. (search)

Autumn started fighting for the right of having clean water at the age of 13.

Autumn (a)   for the right of having clean water since she was 13. (fight)

She watched the documentary before her friends arrived.

She (a)   the documentary when her friends arrived.