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.

[Q]: Sentence1: Plants use unsaturated fatty acids to store energy. 
Sentence2: Plants and fish contain fatty acids.
[A]: Plants


[Q]: Sentence1: propulsion is used for flying by a spacecraft. 
Sentence2: When Apollo 12 took off, the spacecraft was hit by lightning.
[A]: spacecraft


[Q]: Sentence1: Chloroplasts are organelles that are found in the cells of plants and algae. 
Sentence2: Bamboos are vigorous, rugged plants.
[A]:
plants