Investigation is related to Look. Look is related to Active. Active is a synonym of Practical. 
Base is related to Location. Southwest is a type of Location. Southwest is part of West. West is similar to North. 
Investigation <--RelatedTo--> Look <--RelatedTo--> Active <--Synonym--> Practical 
Base <--RelatedTo--> Location <--IsA-- Southwest --PartOf--> West <--SimilarTo--> North 