读对话,完成句子。
A: are you going this afternoon?
B: I am going to the bookstore.
A: ?
B: I'm going to buy a dictionary.
A: are you going?
B: I'm going at 4 o'clock.
A: are you going there?
B: I'm going there by bike.
A: are you going with?
B: I am going there with my sister.