Нужно задать вопросы к выделенным словам: 1)sampson slept in the main building on the first floor. 2)we had cleaned our plates by 7 p.m. 3)raymond has a rider sphere of interest (общий вопрос) 4)the house was built in the 19th century.

1 
What did S do in the main building on the first floor?
Which building did S sleep in? / Where did S sleep? 
On what floor did S sleep?

2
What had we done by 7 p.m.?
What had we cleaned by 7 pm?
By what time had we cleaned the plates?

3
Does R have a rider sphere of interest?

4
When was this house built?
In what century was this house built?