The key (36)____a great camping trip is preparation

The key (36) ……. a great camping trip is preparation. Organizers of the trip need to (37) ……. careful plans about the site, participants and activities. Campers need to prepare for the trip. There is no (38) ……. to bring lots of things, but clothes, sleeping bags, food and (39) ……. aid kits must be available. They should (40) ……. bring their mobile phone to contact their parents