1a) Bill attends Coventry's top medical centre for stress (6) V????T?
9a) Try to persuade an office worker to visit Thailand (5) S???N
15a) A ship takes soldier back before tribe's secret meeting (11) A????N?T??N
11a) Understand about going to a far flung isle (7) E?????E
12d) I need money to get books on time travelling (9) ????E?A?T