demanding       
adjective uk/dɪˈmɑːn.dɪŋ/ us/dɪˈmæn.dɪŋ/
B2 费时费力的,耗费精力的
needing a lot of time, attention, or energy
  She's a very demanding child. 她是个特别不让人省心的孩子。 
 a demanding job/task 艰巨的工作/任务 
 - More examples
 - She's hoping to find a job which is more demanding intellectually.
 - Police work is physically demanding and stressful.
 - My present job doesn't stretch me, so I'm looking for something more demanding.
 - I like a nice light novel to read when I'm on holiday - nothing too demanding.
 - The last part of a piece of music is often more technically demanding than the rest.
 
Opposite: undemanding