"economic growth"; "aspects of social, political, and economical life"
"he wrote the book primarily for economic reasons"; "gave up the large house for economic reasons"; "in economic terms they are very privileged"
"it was no longer economic to keep the factory open"; "have to keep prices high enough to make it economic to continue the service"
"an economic use of home heating oil"; "a modern economical heating system"; "an economical use of her time"
economical 节约的，节俭的。如：He is economical of money and time.
economic 经济(学)的。如：the economic doctrines of Ricardo(李嘉图的经济学说)