Can someone please correct these Japanese exercises I found on the internet? 
1, My father is Japanese. But, my mother is not Japanese. My mother is American.
Watashi no chichi wa Nihon-jin desu. Demo watashi no haha wa Nihon-jin dewaarimasen. Watashi no haha wa Amerika-jin desu.
2, Is Hong-Kong the capital of China? No, Hong-Kong is not the capital of China.
Honkon wa Chuugoku no shuto desu ka. Iie, Honkon wa Chuugoku no shuto dewaarimasen.
3, Is Sumou the Japanese sport? Yes, Sumou is the Japanese sport.
Sumou wa Nihon no supootsu desu ka. Hai, Sumou wa Nihon no supootsu desu.
4, My hobbies are cars and music. My car is a German car.
Watashi no shumi wa kuruma to ongaku desu. Watashi no kuruma wa Doitsu no kuruma desu.
5, The president of my company is my father. I am not the president.
Watashi no kaisha no shachou wa watashi no chici desu. Watashi wa shachou dewaarimasen.