Answer:
Baste /bāst/ verb
1. to cover with liquid before or during cooking.
2. to strike violently and repeatedly.
3. to sew together loosely with large stitches.
His thesis is his most important idea/ideas
(3) Fire, in fact, has been a significant factor in human development and progress in many ways.
This is the main idea. The rest of the sentences support the idea that fire has helped human development and progress. It says that it has allowed humans to "travel into regions that were previously too cold" and "to sleep securely". The passage then continues to talk about how when humans learned to control fire it made significant changes in how long people were able to be productive since they no longer had to rely on the sun for light.
While some people use the internet for cooperation like businesses talking to each other and people can be kind on the internet, the internet can be a very hostile place.