从所给的单词中选出合适的完成对话

Bedroom    watching    beach    letter    reading

Bill: Hello, is that Dad?

Dad: Yes，it's me. How's your holiday? Are you having a good time in Sanya?

Bill: Yes. I'm collecting shells on the now. Where are you, Dad?

Dad: I am in the . I am a book.

Bill: Is Sally TV in the living room?

Dad: No. She is writing a in her bedroom.

Bill: OK. Miss you, Dad. Bye.

Dad: Bye.