You: (ask for your tickets.)
1... tickets to Tower bridge and back, please?
You: ( ask the price) ...?
Assistant: £8.00 for adults and £4.00 for children under 14.
You: (ask about special rates for students) ...?
Assistant: Yes.For students, it's £5.00.
You: (say how many tickets you want for adults, students and children.) ...
Assistant: Can I see your students card(s), please.?
You: (you haven't go it/them with you.) ...
Assistant: I'm sorry, but you have to have a student card to get a reduction.
You: Oh, OK.
Assistant: Here you are.That's your ... altogether, please.