一.选择填空（共15小题，每小题1分，计15分）
1．--Good morning，class!
-- ________!
A．I am fine B．Thank you C．Hello D．Good morning，teacher
2．--What color is the ruler?
-- ________
A．It's a ruler． B．It's white． C．it's white． D．It's a white．
3．--Please sit down．
-- ________．
A．Hello B．Thank you C．Sit down，too D．I'm fine
