下列词语中加线的字，每对读音都完全相同的一组是(　　)

33When a student asks_________it is worth staying up doing their lessons, a teacher may find it difficult to answer

Watch! —I ____ but ____ I ____ anything unusual

It was in the small house _____ was built with stones by his father _____ he spent his childhood.

ets done _______ when people do ittogether,and the rewards are higher too.