Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.

Sentence1: If there is sun, there is sunlight, there is day. 
Sentence2: Energy enters ecosystems from the sun.
sun

Sentence1: Ribosomes are small organelles where proteins are made. 
Sentence2: Ribosomes are assembled inside the nucleus.
Ribosomes

Sentence1: Sight is the ability to sense light, and the eye is the organ that senses light. 
Sentence2: Brown eyes are dominant to blue eyes.

eye