TASK DEFINITION: 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.
PROBLEM: Sentence1: Boiling water can cause burns. 
Sentence2: heating water can cause burns.

SOLUTION: water

PROBLEM: Sentence1: Heat production is increased by shivering and non-shivering thermogenesis . 
Sentence2: Heat production occurs when many muscles contract a little bit all at once.

SOLUTION: Heat

PROBLEM: Sentence1: the gravitational pull of the Moon on Earth 's oceans causes the tides. 
Sentence2: if the Moon were at a greater distance from the Earth, ocean tides would be smaller.

SOLUTION:
Moon