1. We usually have six lectures a week, but last week we had eight lectures.
Here, we are comparing the normal number of lectures per week with a specific week. By using the word "usually," it indicates that six lectures is the regular or typical number. However, last week was different, as it had eight lectures.
2. Last winter was very cold. We had a lot of snow.
In this sentence, it states that the previous winter was exceptionally cold. To support this, it mentions that there was a significant amount of snow. This suggests that the cold weather was intense enough to result in a heavy snowfall.
3. My brother usually has holidays in summer, but he had holidays in autumn last year.
Here, it mentions that typically, the speaker's brother takes holidays during the summer. However, last year, specifically during the autumn season, he had his holidays. This indicates a departure from his usual holiday schedule.
4. They bought a cottage in the country two years ago.
The sentence states that at a specific time in the past (two years ago), they purchased a cottage located in the countryside. This suggests that they acquired a property, likely to spend time away from the city or to have a vacation home.
5. The tourists had a long journey. They were very tired.
These two sentences describe the situation of a group of tourists. It mentions that they took a long journey, indicating a significant distance traveled. As a result, they became very tired, suggesting that the journey was physically exhausting.
6. Kate has a funny dog. Its name is Spot.
This sentence introduces us to Kate and her dog. It describes her dog as funny, suggesting that it has amusing or entertaining behaviors. It further mentions its name, which is Spot.
7. Their room is light. It has three windows.
Here, it describes a room owned by a group of people. The first sentence mentions that the room is light, indicating that it receives a good amount of natural light. The second sentence states that the room has three windows, which is a likely reason why it is well-lit.
8. I am happy because I have a lot of friends.
In this sentence, the speaker expresses their emotion of happiness. They attribute the cause of their happiness to having a large number of friends. This suggests that the speaker finds joy and contentment in their social relationships.
9. It was summer. I had a lot of free time.
The sentence sets the context by stating that it was during the summer season. Then, it mentions that during this time, the speaker had a significant amount of free time. This suggests that the speaker had leisure or spare time due to summer break or vacations.
10. Ann and Bess were at work yesterday. They had a lot of work.
Here, it specifies that the two individuals named Ann and Bess were present at work on a specific day (yesterday). It further elaborates that during this workday, they had a substantial amount of work to complete.
11. Nick is a hunter. He has two dogs.
These two sentences introduce Nick and provide information about him. The first sentence states that Nick's occupation or hobby is hunting. The second sentence mentions that Nick has two dogs, which could potentially aid him in his hunting activities.
Чтобы найти сторону основания ABC правильной треугольной пирамиды SABC, нам понадобятся знания о свойствах правильных треугольников и пирамид. Давайте пошагово разберем эту задачу.
1. Начнем с определения правильной треугольной пирамиды. Правильная пирамида имеет основание, являющееся правильным многоугольником, и все ее боковые грани равны между собой.
2. В нашей задаче треугольник ABC является правильным треугольником.
3. Основание пирамиды ABC является треугольником, поэтому нам надо найти длину его стороны.
4. Центр описанной сферы делит высоту пирамиды на две части: 6 см и 3 см. Это значит, что рассматриваемая пирамида расположена внутри сферы.
5. Для решения этой задачи воспользуемся свойствами сферы. Если проведем радиус, идущий от центра сферы до точки пересечения этой пирамиды с описанной сферой, он будет являться высотой пирамиды.
6. Так как пирамида правильная, то высота и радиус сферы будут перпендикулярны. То есть, рассматриваемая высота будет являться и высотой треугольника ABC.
7. Для удобства, назовем точку пересечения пирамиды с описанной сферой точкой M.
8. Теперь, когда мы знаем, что AM является высотой треугольника ABC, а разбивка высоты пирамиды на две части равна 6 см и 3 см, мы можем записать уравнение: AM = 6 см + 3 см = 9 см.
9. Далее, рассмотрим прямоугольный треугольник AMS, где S - центр описанной сферы. Согласно теореме Пифагора для этого треугольника, сумма квадратов катетов равна квадрату гипотенузы.
10. Катет MS равен радиусу сферы, который мы обозначим буквой R.
11. К сожалению, мы не знаем R (радиус сферы) и BC (сторона треугольника ABC). Однако, у нас есть возможность найти R через BC с помощью знания, что центр сферы делит высоту пирамиды на две равные части.
12. Подумай, как можно связать R и BC, зная, что M делит высоту на две равные части.
Ответ на эту задачу не может быть найден только на основе предоставленных данных. Нам необходима дополнительная информация, чтобы найти сторону основания ABC пирамиды.
Here, we are comparing the normal number of lectures per week with a specific week. By using the word "usually," it indicates that six lectures is the regular or typical number. However, last week was different, as it had eight lectures.
2. Last winter was very cold. We had a lot of snow.
In this sentence, it states that the previous winter was exceptionally cold. To support this, it mentions that there was a significant amount of snow. This suggests that the cold weather was intense enough to result in a heavy snowfall.
3. My brother usually has holidays in summer, but he had holidays in autumn last year.
Here, it mentions that typically, the speaker's brother takes holidays during the summer. However, last year, specifically during the autumn season, he had his holidays. This indicates a departure from his usual holiday schedule.
4. They bought a cottage in the country two years ago.
The sentence states that at a specific time in the past (two years ago), they purchased a cottage located in the countryside. This suggests that they acquired a property, likely to spend time away from the city or to have a vacation home.
5. The tourists had a long journey. They were very tired.
These two sentences describe the situation of a group of tourists. It mentions that they took a long journey, indicating a significant distance traveled. As a result, they became very tired, suggesting that the journey was physically exhausting.
6. Kate has a funny dog. Its name is Spot.
This sentence introduces us to Kate and her dog. It describes her dog as funny, suggesting that it has amusing or entertaining behaviors. It further mentions its name, which is Spot.
7. Their room is light. It has three windows.
Here, it describes a room owned by a group of people. The first sentence mentions that the room is light, indicating that it receives a good amount of natural light. The second sentence states that the room has three windows, which is a likely reason why it is well-lit.
8. I am happy because I have a lot of friends.
In this sentence, the speaker expresses their emotion of happiness. They attribute the cause of their happiness to having a large number of friends. This suggests that the speaker finds joy and contentment in their social relationships.
9. It was summer. I had a lot of free time.
The sentence sets the context by stating that it was during the summer season. Then, it mentions that during this time, the speaker had a significant amount of free time. This suggests that the speaker had leisure or spare time due to summer break or vacations.
10. Ann and Bess were at work yesterday. They had a lot of work.
Here, it specifies that the two individuals named Ann and Bess were present at work on a specific day (yesterday). It further elaborates that during this workday, they had a substantial amount of work to complete.
11. Nick is a hunter. He has two dogs.
These two sentences introduce Nick and provide information about him. The first sentence states that Nick's occupation or hobby is hunting. The second sentence mentions that Nick has two dogs, which could potentially aid him in his hunting activities.