19.He was busy writing a story,only _______ once in a while

19.He was busy writing a story,only _______ once in a while 1.He was busy writing a story,only once in a while to smoke He was busy writing a story, only ____ once in a while to sm he was busy writing a story,olny stopping once in a while to He was busy writing a story ,olny ( ） once in a while to smo [-A59] He was busy writing a story ,only ______ once in a wh 非谓语动词 伴随状态He was busy writing a story ,only _____ once in a He was busy writing a story,only ( stopping ) once in a whil He was busy writting a story ,only stopping once in a while He was busy writing a story,only ____... He was busy repairing the computer ,only ____once in a while He was busing writing a story,only___once ina while to smoke