Preserve is related to Keep. Keep is related to Reserve. Reserve is related to Left. Left is related to Signal. 
Achieve is a synonym of Complete. Complete is related to Comprehensive. 
Preserve <--RelatedTo--> Keep <--RelatedTo--> Reserve <--RelatedTo--> Left <--RelatedTo--> Signal 
Achieve <--Synonym--> Complete <--RelatedTo--> Comprehensive 