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: poisonous darts are used for defense by sea anemones. 
Sentence2: poisonous darts are used for protection by sea anemones.
anemones

Sentence1: healing requires rest. 
Sentence2: Healing and cell regeneration follows.
healing

Sentence1: Any green plant can be considered for use in the production of biofuel or bioenergy. 
Sentence2: Green plants can be used to produce electricity by burning.

green