hopefulness       
noun [ U ] uk/ˈhəʊp.fəl.nəs/ us/ˈhoʊp.fəl.nəs/
 满怀希望
the feeling or state of having hope
  He blends optimism and hopefulness with a strong sense of irony. 他将乐观和希望与强烈的讽刺感融为一体。 
 The show hasn't lost its charm or its sense of hopefulness. 这个节目并没有失去它的魅力和它的希望感。 
 See: hopeful
 - More examples
 - After the training, 22 percent reported increased feelings of hopefulness.
 - He expressed hopefulness but sounded somewhat guarded and sceptical.
 - His tone implied something more than mere hopefulness.