Найти и отметить герундии Sonar (sound navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances (ranging), communicate with or detect objects on or under the surface of the water, such as other vessels.[2] Two types of technology share the name "sonar": passive sonar is essentially listening for the sound made by vessels; active sonar is emitting pulses of sounds and listening for echoes. Sonar may be used as a means of acoustic location and of measurement of the echo characteristics of "targets" in the water. Acoustic location in air was used before the introduction of radar. Sonar may also be used for robot navigation,[3] and SODAR (an upward-looking in-air sonar) is used for atmospheric investigations. The term sonar is also used for the equipment used to generate and receive the sound. The acoustic frequencies used in sonar systems vary from very low (infrasonic) to extremely high (ultrasonic). The study of underwater sound is known as underwater acoustics or hydroacoustics.]
The first recorded use of the technique was by Leonardo da Vinci in 1490 who used a tube inserted into the water to detect vessels by ear.[4] It was developed during World War I to counter the growing threat of submarine warfare, with an operational passive sonar system in use by 1918.[2] Modern active sonar systems use an acoustic transducer to generate a sound wave which is reflected from target objects.[2]

Упражнение 2 Пользуясь таблицей, переведите предложения в косвенную речь (добавьте нужное слово)

1 Dan said "Tina will arrive tomorrow" - Dan said that Tina would arrive the next day.

2 Ben said "I have sent the email this week" Ben said that he had sent the email that week.

3 The kids said " We lost the game yesterday"- The kids said that they

had lost the game the previous day.

4 Susan says "Travelling is an exciting experience". - Susan says that travelling is an exciting experience.

5 Joe said "The trip to mountains was a perfect escape". Joe said that the trip to mountains had been a perfect escape.

6 Mum said "Granny is watering the flowers in the garden now" - Mum said that Granny was watering the flowers in the garden ＿

7 The newspapers report "The world temperature is rising'- The newspapers report that the world temperature is rising.

8 The reporter said "Texting is not really popular now"- The reporter said that texting

was not popular then.

9 Anna said "I spent a lot of time on the Internet as a teen"- Anna said that had spent

a lot of time on the Internet as a teen.

10 He said 'I have uploaded some materials today"- He said that had uploaded some materials that day.

ответ:Photo 3.

  The boy in the photo is doing homework in the kitchen. Sitting on a chair, he looks at his homework in an electronic diary. After viewing the homework, it will start to complete it. He is very focused on this slave. The black-haired boy is dressed in a bluish t-shirt, his age is 11 years. I liked the picture. It makes me feel like a child.

Объяснение: Это перевод

Фото 3.

Мальчик на фотографии делает домашнюю работу на кухне. Сидя на стуле, он смотрит домашнюю работу в электронном дневнике. После просмотра домашней работы, он приступит к его выполнению. Он очень сконцентрирован над этой рабой. Черноволосый мальчик одет в голубоватой футболке, возраст его 11 лет. Мне понравилась картина.  В ней я ощущаю себя как в детстве.