Найдите ошибки в предложениях: what is he talking? it is often raining in autumn my friend which lives in st petersburg is a student my mother works at home, so she mustnt't go to her office every day children don't have to swim here without an adult what rainy day! let's play indoors the bridge is a built last year the russian is spoken by millions of people more than 100 millions people speak japanese you may not ride a bike here. it is dangerous

What is he talking about?
It often rains in autumn.
My friend who lives in St. Petersburg is a student.
My mother works at home, so she neednt't go to her office every day.
Children mustn't swim here without an adult.
What a rainy day! Let's play indoors.
The bridge was built last year.
Russian is spoken by millions of people.
More than 100 million people speak Japanese.
You should not ride a bike here. It is dangerous.