My house burned down completely last night.

The window is wide open, and fresh air is flowing into the room.

I opened the window all the way.

Since my grades in the first semester were not good, I have to work harder in the second semester.

We discussed the new project at the last meeting.

All lines have been resumed operation.

He was hiding his criminal record.

Natural selection plays an important role in the evolution of organisms.

He was on the verge of despair.

He is applying his experience from his former post to his new job.