sensation is to detection as perception is to interpretation. Reason: When we detect something, we sense it. Similarly, when we have some perception in our mind, we interpret it.

tree is to climb as ocean is to swim. Reason: we climb on tree and swim in ocean.

tree is to forest as grass is to lawn. Reason: Trees grow in forests. Similarly, grass grows in lawns.

brightness is to light as loudness is to sound. Reason: Bright and light are synonymous terms. Similarly, loudness and sound are synonyms.

Brightness is to intensity as hue is to wavelength. Reason: brightness is measured in intensity (more the intensity, more is the brightness). Similarly, hue is measures in wavelength.