根据对话内容，用方框中所给单词的适当形式填空。

he    Helen   for   about    pencil

Teacher: Hi, Anna. Are these your ?

Anna: No, they're Bob's.

Teacher: And is this his green pen?

Anna: No, it isn't. The blue pen is .

Teacher: What this dictionary?

Anna: It's . And the green pen is hers, too.

Teacher: And the eraser? Is that yours?

Anna: Yes, it is.

Teacher: Thank you your help, Anna.

Anna: You're welcome.