The soldiers had just moved to the desert, and as they had never been in such a place before, they had a lot to learn. As there were no trees or buildings in the desert, it was, of course, very hard to hide their trucks from enemy planes. The soldiers were, therefore, given training in camouflage. They were shown how to paint their trucks in irregular patterns with pale green, yellow, and brown paints, and then to cover them with nets to which they had tied small pieces of cloth. The driver of the biggest truck had a lot of trouble camouflaging it. He spent several hours painting it, preparing a net and searching for some heavy rocks with which to hold the net down. When it was all finished, he went for lunch. When he came back from his meal, he was surprised and worried to see that his camouflage was completely spoilt by the truck's shadow, which was growing longer and longer as the afternoon advanced. He stood looking at it, not knowing what to do. Soon an officer arrived, and he, too, saw the shadow, of course. "Well," he shouted to the poor driver, "What are you going to do about it? If an enemy plane comes over, the pilot will at once know that there is a truck there." "I know, sir," answered the soldier. "Well, don't just stand there doing nothing!" said the officer. "What shall I do, sir?" asked the poor driver. "Get your spade and throw some sand over the shadow, of course!" answered the officer. The soldier was surprised and worried because   _  .
his truck had cast a shadow in the sun and the enemy plane would find it. the shadow of his truck was growing longer at noon it was late in the afternoon, and he could not get rid of the shadow his newly-painted truck was in the shadow