Romaji
Watashi no namae wa Mayumi desu.
Watashi no chichi no namae wa Kenta desu.
Watashi no haha wa Kimie desu.
Karera wa kanojo no tomodachi desu ka？
- Iie,chigaimasu.
Kore wa anata no kaban desu ka？
Hai, kore wa watashi no kaban desu.
Kore wa kare no hon desu ka？
- Iie, kore wa kanojo no（hon）desu.
English
My name is Mayumi.
My father’s name is Kenta.
My mother is Kimie.
Are they their (female) friends?
– No, it is not true. ← This might sounds funny in English, but we can say this way in Japanese.
Is this your bag?
– Yes, this is my bag.
Is this his book?
– No, this is hers.
Explanations from Wikipedia
Expressing Possession Using Particle no (の)
The particle no (の) is used to express possession, either figuratively or literally, of one noun phrase by a second noun phrase, by indicating that the noun proceeding no is the possessor, and the noun following is the possessee.
The possessee can be pronominalised by replacing it with either mono (もの), which translates as ‘one’, as in ‘John’s one’. Japanese often omits proper nouns and subjects once they have already been mentioned in a conversation, and which are then understood through context.
So now you can say things like…
わたし の いぬ の ボブ の おもちゃ は わたし の くつした です。
Watashi no inu no Bob no omocha wa watashi no kutsushita desu.
My dog Bob’s toy is my socks.