콤마와 that

The price increases, ?that were intended to fill holes in state budget, could keep more than half a milion kids~~~~

이런문장인데요 콤마 댓이
안되서 저기?부분이틀렸다는데
삽입절은생략되는형태니까 콤마댓써도괜찮은거아닌가요?~~
그냥 문장이 ----,----. 꼴일땐 콤마that 쓸수없는건아는데 삽입절은....
알려주세용!