Giúp mình với Many of the UFO stories that we read about in the papers are based on the reports of people who have been on their own when they (1) ___

Giúp mình với
Many of the UFO stories that we read about in the papers are based on the reports of people who have been on their own when they (1) ___ the event occurred, (2) ___ we only have word that what they saw really happened.
(3) ___, when mystery lights appeared in the distance over the sea in Lincolnshire, the police, the Air Force, coast guards and a tanker out at sea managed to witness what occurred. It was 3.14 in the morning when police reported (4) ___ an unrecognizable red and green rotating light in the sky. It made no sound. At 3.31 am, the RAF confirmed that there were in fact two unidentified objects. At 7.08 am, it became known that a civil aircraft had also seen these strange lights. Several fascinating facts were revealed (5) ___ this investigation. (6) ___ man-made flying objects carry ‘transponders’ which (7) ___ them to be identified but these mystery objects had (8) ___. The crew of the (9) ___ tanker, who had the best view of the objects, recalled watching the lights for 4 or 5 hours and rejected the idea that they could have been (10) ___ by weather conditions, There was no storm in the area that would have prevented them from seeing clearly. So, were they really UFOs? You’ll have to make up your own mind!
1. a. speak b. talk c. tell d. say
2. a. unless b. so c. while d. if
3. a. Because b. Since c. However d. Despite
4. a. staring b. looking c. glancing d. seeing
5. a. within b. during c. for d. across
6. a. Whole b. Both c. All d. Entire
7. a. make b. let c. allow d. give
8. a. neither b. no one c. nothing d. none
9. a. near b. close c. next d. nearby
10. a. discovered b. caused c. developed d. noticed