Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct word or phrase that best fits each of the numbered blanks.

Drone racing is an exciting new sport that has become popular faster than (29)______ other sport before it. Pilots steer small and lightweight, but high-powered drones along courses with obstacles. They fly through gates and around flags at speeds of over a hundred miles an hour. They control the drones using VR-like headgear. Every drone has a camera (30)________ to it so that spectators can also view flights either on a big screen or with special headgear. The races take place either outdoors - in big stadiums, or indoors in old warehouses and sports arenas. (31)________ are short because the battery time of drones is limited. (32)_______ drone racing started only a few years ago, there are already international competitions that take place all over the world. In professional leagues, drone pilots compete for thousands of dollars. In March, the World Drone Prix was staged in Dubai. A 16-year-old British teenager not only one the race but also received a prize money of 250 000 dollars. Television and other media have become aware of drone racing. ESPN, an American sports channel, will be broadcasting international drone races starting this August. Races are also recorded and uploaded to YouTube and other video platforms (33)________ they can be viewed over and over again.

This species of African elephants is_______.

________, the more he likes it.

For a moment, at_______ sight of a bunch of beautiful flowers, she suddenly felt content.

He tried to join the army but he was turned in because of his poor health.

This interesting book _______ by many students every day.

Johnny has a really big mouth. You can't tell him anything or the whole world will know about it.

We shouldn't make an appointment with this doctor. You can see him whenever you want.

Throughout history, various people have demonstrated a high degree of confidence in the ability of certain animals to predict the weather. It may seem surprising today in view of the complex equipment now involved in weather forecasting to understand that in certain cases, the behavior of animals does indeed provide an indication of inclement weather. Sensitivity of certain animals to falling air pressure or to low-frequency sound waves that humans cannot hear, which are indicators of approaching storms, causes behaviors in animals that certain societies have come to recognize as predictors of storms.

A number of animals are remarkably sensitive to variations in air pressure, and some of these animals show consistent, noticeable, and predictable behaviors as air pressure drops before a storm hits. When the air pressure drops before a storm, some animals move closer to the ground to equalize the pressure in their ears: some birds such as swallows tend to stay on the ground or roost in trees instead of soaring in the skies when a storm is imminent because of the decreasing air pressure. Other animals make more noise than usual as air pressure drops: an unusual amount of quacking by ducks and a high volume of croaking by frogs are both indicators that are believed to occur because of the high degree of sensitivity of ducks and frogs to the change in pressure. Finally, still other animals become more active before storms as a reaction to the falling air pressure: dolphins and porpoises seem to be taking part in a frenzied sort of play, and bees and ants become more active prior most likely because of their sensitivity to lower pressure.

There is good reason to believe that the fact that these animal behaviors seem to occur regularly prior to storms may have a scientific basis and that the animals demonstrating these behaviors may actually be good short- range weather forecasters. However, their ability to predict long-range weather patterns is rather suspect. Certain proverbs, for example, are based on what is most likely the idea that squirrels are good indica weather patterns. One proverb indicates that, if a squirrel seems busier than usual in gathering nuts, then a long and cold winter is on its way; however, this behavior in squirrels is more likely due to a large supply of nuts available for gathering, which occurs because of earlier good weather, and is not an indicator of cold weather to come. Another proverb about squirrels indicates that if a squirrel grows a long and bushy tail in the fall, then a particularly harsh winter is on its way; in this case too, the squirrel develops a long and bushy tail because of earlier good weather and not as a warning of bad weather to come.

(Adapted from TOEFL Reading Practice by Deborah Philips