2. The Browns last painted the living-room two years ago. → The Browns have painted the living room for two years.

3. Why don't we join them on the trip to the mountain? → I suggest joining them on the trip to the mountain.

4. We must be grateful to all the teachers. They have helped us a lot in our lives. → We must be grateful to all the teachers who have helped us a lot in our lives.

5. He actively participated in the fight against air pollution. → He was an active participant in the fight against air pollution.

2. The Browns have not painted the living-room for two years.

3. I suggest joining them on the trip to the mountain.

4. We must be grateful that all the teachers have helped us a lot in our lives.

5. He actively took part in the fight against air pollution.

#NoCopy