English Conversations: Railway Travel - A ticket to London, please.

Paul Reyfield: What time does the  next train to London leave?    
Railway Station Clerk: At 16:35, from platform 8    
Paul Reyfield: Is it a direct train to London?  
Railway Station Clerk: No, you have to change trains at Birmingham.    
Paul Reyfield: I see.One ticket to London, please.    
Railway Station Clerk: Single or return, sir?    
Paul Reyfield: Single,please.    
Railway Station Clerk: 64 pounds, please.    
Paul Reyfield: Here you are.  
Railway Station Clerk: Here is your ticket and change, sir.