Fill in the blanks, each using one of the given words or phrases

Fill in the blanks, each using one of the given words or phrases below in its proper form.
all at once   adept at   specialize in   wind up   in the justification of   what’s more   doomed to   applicable to   accrue to   opt for   in common   submit to
My sister is very_________ making people at their ease.
【正确答案】：adept at