My home's front entrance consists of several big stones. There are some gaps betweens the big stones. Please suggest solutions to the problems. The gap as shown in the attached files 1 and 2 is between concrete and stone, should I cover the gap with concrete? The gaps as shown in the attached files 3, 4 and 5 are between adjacent stones. I had moved the stones last year horizontally so that there are no gaps. However, the gap reappear this year. Another problem is that the stones are not even vertically. I had moved the stones last year and leveled the small stones underneath, then moved the stones back. However, the stones become uneven vertically again this year.