question: unsure about which type of ksh file you have? do you want to know exactly what it is, who created it, and how to open it?
Capitalize this past sentence correctly.
A: Unsure about which type of KSH file you have? Do you want to know exactly what it is, who created it, and how to open it?

question: if you have a referral
Capitalize this past sentence correctly.
A: If you have a referral

question: his main work focused on the theory of analytic functions.
Capitalize this past sentence correctly.
A: His main work focused on the theory of analytic functions.