Read these sentences and fill in the gaps with the correct variant (must, mustn’t, have to, don’t have to, doesn’t have to or has to).

2.You
return these shoes. They are too small for you.

3.All the students
follow the school rules.
​

ответ: ...have finished my homework...

Объяснение:

Здесь мы используем present perfect, так как, предположительно, действие завершилось (выполнение д/з) совсем недавно. По правилу в этом случае мы используем Present Perfect.

"Had finished" будет неверно, потому что Past Perfect используется, когда нужно передать, что действие выполнилось до какого-либо другого действия. Например, "I had done my homework before I went for a walk with my friends". Я выполнил домашку до того момента, как пошел погулять с друзьями.  

It is not a secret that our meals influence much on our health and our mood. That’s why I consider breakfast to be the most important meal in the day as it is the first our meal and it can put us in good spirits or it can’t. Now I shall tell you about my breakfast. 
In the morning I usually have porridge. I often start my breakfast with a cereal which is not cooked, it is something dry, ready to be eaten or muesli – some grain or porridge which is not cooked with dried fruit, nuts and so on. 
I also like eggs (cooked in different ways). I don’t practically eat butter, I prefer soft margarine – made of vegetable fat, which is not heavy and creamy. I don’t eat jam at breakfast, I eat marmalade which is not sweet, there is slight bitterness; it’s rather pleasant. 
I usually don’t have substantial breakfast on weekdays, I do it on weekends when I get up late. Very often I have just tea or coffee with sandwiches. Tea is usually taken by me with milk. I like very strong tea without sugar. 
Sometimes when I am in hurry I don’t have time to have proper breakfast and I go to the university being hungry. In such case I usually buy something like «Snickers» or «Mars» on my way to the Alma Mater.