instruction:
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.
question:
Sentence1: cell division often causes growth. 
Sentence2: Cell division leads to reproduction.
answer:
cell


question:
Sentence1: Nonmetal elements are far fewer in number. 
Sentence2: There are 17 nonmetals on the periodic table.
answer:
Nonmetal


question:
Sentence1: a compass is used to navigate oceans. 
Sentence2: Navigation by compass is especially difficult during a magnetic storm.
answer:

compass