mainstay [ˈmenˌste]

例句:

• It has been the mainstay for the DC area.
  来自VOA
• The mainstay of treatment is pain relief such as paracetamol.
  来自BBC
• Cocoa is the country's economic mainstay.
  可可是这个国家的经济支柱。
  
• Agriculture is still the mainstay of the country's economy.
  农业仍然是这个国家经济的主要支柱.
  
• After the father's death the son became the mainstay of the family.
  父亲死后,儿子就成了这个家庭的主心骨.
  
• It's a mainstay for writers and artists.
  来自WSJ