Stem is a type of Tube. Tube is related to Train. Trainer is derived from Train. Trainer is a type of Worker. 
Excellent is related to Outstanding. Outstanding is related to Field. Field is related to Desert. 
Stem --IsA--> Tube <--RelatedTo--> Train <--DerivedFrom-- Trainer --IsA--> Worker 
Excellent <--RelatedTo--> Outstanding <--RelatedTo--> Field <--RelatedTo--> Desert 