请根据所给句子的内容，从下面的方框中选出适当的词，并用其正确的形式填在答题卡相应的横线上。每空一词，每词限用一次。

— Will Mr. Black be here soon?

— I’m not sure. Let’s go and see         .

A．when will the train arrive

B．when the train will arrive

C．when the train will arrive at

D．when will the train arrive at

— I wonder _ _.

— I'm afraid we'll be late.

A. how we can be on time                B. what we are going to do

C. why we get to school late            D. if we will arrive at the meeting on time

— I wonder _ _.

— I'm afraid we'll be late.

A. how we can be on time                B. what we are going to do

C. why we get to school late            D. if we will arrive at the meeting on time

— I wonder _ _.

— I'm afraid we'll be late.

A. how we can be on time                B. what we are going to do

C. why we get to school late            D. if we will arrive at the meeting on time