Complete the text with 'when' or 'while'.

1. While Pops, Eva and Mac were cycling through the desert, they saw a tomb. 2. They were trying to find a way into the tomb when Pops saw a small door. 3. They went inside. Pops and Mac were looking at the walls of the tomb while Eva was trying to put on the necklace. 4. She was screaming when somebody touched her neck. 5. Mac was standing near Eva while she screamed. 6. Then they saw Princess Zara! While they were running out of the tomb, they dropped the necklace.