(Bijutsukan e itte kimasu.) - I am going to the art museum and coming back. Exercise 4: ~ておく (Preparation Action)
(Ryokō no mae ni, kippu o katte okimasu.) - I will buy the ticket before the trip. minna no nihongo lesson 43 renshuu b answers
Used to describe something that looks like it is about to happen (e.g., "It looks like it will rain"). (Bijutsukan e itte kimasu