When is better to use "aye" instead of "yes"? Is it an antiquated expressoin?

Help me please. Find the mistake in the sentence. 1. Extreme wealthy and poverty can be seen in many developing countries. 2. Luckily, they have found cure for this awful disease. 3. I think my standard living has improved since I came to this country. 4. I don't like the city because there is too much polluted. 5. Fortunately the mortal rate has fallen in recent years. 6. The use of solar power can help to reduce global warmings. (I think in this case "warming" is right. Am I right?) Thank you!!

What to visit in London? I'm flying to London next week. What do you advise to visit? (Time to be a little)

Victory parade Road closed today in my city, because tanks drove through the city... This is a victory parade, the memory of World War II. These memories are very hard for many people... But today it's very beautiful and exciting spectacle. When the tanks go by the earth shakes, when firing the gun, buzzing in the ears... It was really great!!

My weekend Hi, everybody. I have a gread weekend! 3 days! Yahoo! Yahoo-ho!! I'll relax in the natute. Have a nice weekend!