Read the passage below and choose one correct answer for each question.

Transport in London is expensive. The fare depends on the length of the journey;  you cannot buy or book tickets in advance. Children under sixteen pay half, and those under five travel free.

You usually buy bus tickets from the conductor, but some buses you pay the driver. Most London buses are double-deckers. On the underground railway (or tube) you buy your ticket from the machine or ticket office, and give it up at the end of the journey. Not all trains from one platform go to the same place, so watch the signs. The fast train leaves at 1.15 p.m.

Children under five don’t have to.....................when they use public transport.