помогите, пожалуйста, очень надо используя косвенные вопросы тоесть в более вежливой форме составить предложения они должны начинаться с do you know ..пример why did ancient people
leave arkaim--------------- do you know why ancient people leave. Обратите внимание на did я не знаю что с ним делать

вот сами
предложения       
1.       
where is he
2       when did you see the explosion 
3       
why did it disappear
4       what have the scientists found in the
sea                                                              

1.Do you know where is he going? 2. Do you know when did you see the explosion? 3. Do you know why did it disappear? 4. Do you know what have the scientists found in the river? Did используется в Past Simple

1. Do you know where he is?2. Do you know when you saw the explosion?3. Do you know why it disappeared?4. Do you know what the scientists have found in the sea?