Какая разница между "have you known" и "do you know". Да, я знаю, что первое - present perfect, а второе - present simple, но вот сам смысл как-то меняется? В русском языке, вроде, нет: "Знал ли ты?" и "Знаешь ли ты?", можно сказать, одинаковы, а как дела с этим обстоят в английском?​

Как мне кажется, разница скорее в том, что "Have you known" ставится перед каким-то фактом и т.п. То есть, "А знали ли вы, что...".

А "Do you know", идет на выпытывание, а-ля "А ты знаешь?" Без дальнейшего потока информации. Как "Не могу решить задачу, знаешь ответ?"

Надеюсь, натолкнул на какие-то размышления.

Questions: 
1. The weather in England is very changeable, isn't it? Yes, it is.
2. What comparison do the English use when they want to describe a person whose mood and opinion changes very often? The English use the comparison "as changeable as the weather" of a person who often changes his mood or opinion about something. 3. What statement is often made by the English to describe the meteorological conditions of their country? This statement "Other countries have a climate; in England we have weather" is often made by the English to describe the meteorological conditions of their country. 

4. How often does it rain in England? It often rains in England. The English have three variants of weather: when it rains in the morning, when it rains in the afternoon, or when it rains all day long. 
5. The weather is the favourite conversational topic in England, isn't it? Yes, it is. Do you find this topic of conversation interesting? No, I do not.
6. What is the best time of the year in England? The best time of the year in England is spring.
7. What do you know about London fogs? The most unpleasant aspects of the weather in England are fog and smog.
8. What kind of weather do you like best of all? I like sunny weather.
9. Where do you get the weather forecast from? I get the weather forecast from the Internet. Do you always believe it? No, I do not.

1. Will, they, go, will
2. You, will, come, won’t, you
3. Will you come to see us when you are in Moscow again?
4. finishes, for
5. You, will, be, won’t, you
6. If I help you, will you complete this work tomorrow?
7. Are, a, am
8. a lot of
9.  Will, they, come, won’t
10. a few, many
11. There, a pen
12. have, you
13. a few
14. many, have, got
15. a few
16. The, is
17. live, will swim
18. They went, didn’t they
19. a great effort
20. только в настоящем времени
21.  Ann will go, won’t she
22. Your friends will do, won’t they
23. Your sister will go, won’t she, she will
24. There will be many people
25. many, did, have