Use either should/shouldn’t or must/mustn’t in the following sentences. — Используйте либо следует / не следует или должны / не должны в следующих предложениях. 1. Everyone must be here by 8 o’clock

13 11 9 7 5 3 1
я не уверен но кажется все верно

C 19-ой по 14-ую ступень он спускался нормально.
Далее с 14-ой на 12-ую -> 10 -> 8 -> 6 -> 4 -> 2 -> 0

Пропустил: 13, 11, 9, 7, 5, 3 и 1-ую ступеньки.

Everyone must be here by 8 o’clock.
"Каждый должен быть здесь к 8 часам"

In this sentence, we use "must" because it is an obligation or a requirement for everyone to be present before 8 o’clock. The word "must" expresses a strong sense of necessity and emphasizes the importance of arriving on time. It shows that it is mandatory for everyone to be present by 8 o’clock, and there are no exceptions or alternatives.

You could also use "should" or "shouldn’t" in this sentence, but the meaning would be slightly different.

If we use "should," the sentence would be:
"Everyone should be here by 8 o’clock."
"Каждый следует быть здесь к 8 часам"

In this case, "should" implies a recommendation or advice. It suggests that it would be a good idea for everyone to be present by 8 o’clock, but it is not necessarily mandatory. It leaves some room for flexibility or personal choice.

On the other hand, if we use "shouldn’t," the sentence would be:
"Everyone shouldn’t be here by 8 o’clock."
"Каждый не следует быть здесь к 8 часам"

In this case, "shouldn’t" implies that it is not recommended for everyone to be present by 8 o’clock. It suggests that there might be some negative consequences or disadvantages if everyone arrives at that time. It is a suggestion to avoid being present by 8 o’clock.

However, the given sentence emphasizes the importance of everyone being present by 8 o’clock. Thus, "must" is the most appropriate choice in this context.