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: Spikes are forceful the tidal waves of electric current. 
Sentence2: spikes come from tidal energy.
Spikes

Sentence1: Most pituitary hormones control other endocrine glands. 
Sentence2: Hormones tell the ovaries to produce eggs.
hormones

Sentence1: Balance is the ability to sense and maintain body position. 
Sentence2: Balance is critical.

Balance