QUES: There has to be a development in our inner life

correct the punctuation.

CORRECTED: There has to be a development in our inner life."

QUES: In about two months December and January he made more discoveries that changed the world than anyone has ever made before or since

correct the punctuation.

CORRECTED: In about two months, December and January, he made more discoveries that changed the world than anyone has ever made before or since.

QUES: The rooms are spacious and its decor is minimalist the neutral colors give a sophisticated touch that fits perfectly its quality furniture

correct the punctuation.

CORRECTED:
The rooms are spacious and its decor is minimalist, the neutral colors give a sophisticated touch that fits perfectly its quality furniture.