سؤال إنجليزي للصف السابع في القراءة والاستيعاب

Another mystery that we can't explain is the Hessdalen Lights. These bright lights are sometimes seen in the sky above a valley in Norway. They go on and off and they move around the sky or down the valley. They can be as large as cars. Scientists can't agree on what makes these lights, so they are still a mystery!