Check out example codes for "in line a frame animation". It will help you in understanding the concepts better.

Code Example 1

<a-sphere animation="property: rotation; from: 0 0 0; to: 270 0 90;"
          animation__2="property: position; from: 0 0 0; to: 2 -2 8;"
          animation__color="property: material.color; from: #fff; to: #555;"></a-sphere>

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