question: perhaps no other decade has contributed more to the development of the truck than the 1950s. petrol engines and rudimentary pre-chamber-combustion diesel engines were superseded by efficient direct-injection diesel engines.
Capitalize this past sentence correctly.
A: Perhaps no other decade has contributed more to the development of the truck than the 1950s. Petrol engines and rudimentary pre-chamber-combustion diesel engines were superseded by efficient direct-injection diesel engines.

question: what microbes cause septic arthritis?
Capitalize this past sentence correctly.
A: What microbes cause septic arthritis?

question: walking quietly through the different districts and nice restaurants, shops and restaurants discover i still find the most fun to do.
Capitalize this past sentence correctly.
A: Walking quietly through the different districts and nice restaurants, shops and restaurants discover I still find the most fun to do.