( ) — ，where's the book?
—I'm sorry. I don't know.
A. Excuse me B. I'm sorry C. Sorry
( ) We having an English lesson.
A. / B. are C. can
( ) Let's read .
A. book B. a book C. the book
( ) —Happy birthday!
— .
A. Excuse me B. No，I'm not happyC. Thank you
( ) — I come in?
—Come in，please.
A. Do B. Am C. May