to take a lot of effort

• 费力的活儿

  tiring work

• 费力不讨好

  difficult and unrewarding

• 费力劳心

  physically and mentally strenuous

• 不用怎样费力就能学会。

  It can be mastered without much effort.

• 他做工作从来不怕费力。

  He is never afraid of hard work.

• 他有气喘病，说话很费力

  talking is strenuous for him because of his asthma