Plant is part of Ecosystem. Grass is a type of Plant. Grass is related to Animal. you are likely to find Muscle in/at/on Animal. 
Reflection is related to Glass. Glass is related to Telescope. Telescope is related to Astronomer. 
Ecosystem <--PartOf-- Plant <--IsA-- Grass <--RelatedTo--> Animal <--AtLocation-- Muscle 
Reflection <--RelatedTo--> Glass <--RelatedTo--> Telescope <--RelatedTo--> Astronomer 