No one in my class is more beautiful than Mary. Mary is the most beautiful girl in my class.

My house is larger than his house. His house is smaller than mine.

Susan is taller than the other two girls. Susan is the tallest of the three girls.

He started to learn to drive when he was 18. He has been learning to drive since he was 18.

I last met him 2 years ago. I haven't met him for 2 years.

The last time I wrote to him was two years ago. I haven't written to him for two years.