1. Thay asked the customers:” visit our new shop in Moscow!” 2. They sign tells everybody:” don’t walk on the lawn!” Перевести в косвенную речь

They asked the customers if they visited their new shop in Moscow.
The sign tells everybody if they didn’t walk on the lawn.

Видимо, Вы столкнулись с разными акцентами. Люди, живущие в разных странах и даже в разных районах одной страны многие слова произносят довольно-таки по-разному. Даже в одной Великобритании выделяют не один десяток акцентов. Поэтому сложно сказать, что считать нормой.
Мы в школах изучаем стандартное принятое британское произношение, которое не привязано к одному определенному региону.
Слово стоп, к примеру, по-разному может произноситься британцами и американцами.
амер.  [stɑːp]  (через "а") брит.  [stɒp]  (через "о")

Тем, кто не оригинальный носитель языка, а изучает его как иностранный, лучше учить как в словаре)))

1. Mary has typed a lot of documents. 2. Megan has seen many places. 3. Mr. Tompson has made many good films. 4. Sarah has translated a lot of foreign novels. 5. Mrs. Stone has written ten novels and twenty short stories.

1. It has'n been... . Has it been...? 2. They haven't been... . Have they been...? 3. Sam hasn't been... . Has Sam been...? 4. He hasn't been... . Has he been...? 5. Mr. White hasn't been... . Has Mr. White been...?

1. He must be in his cabinet now. 2. May I come in? - Yes, please. 3. You must read this text. 4. May I ask you? - Yes, please. 5. I can't go to the cinema with you, cause I'm very busy.

1. Teacher said us to go home. 2. My mother said me to buy meat in the shop. 3. Alice said her friend lived in London. 4. The teacher said to me I had not done the work well. 5. I said to Nick where he was going. 6. I said to Boris if his friend lived in Moscow.