B呀
是一个固定的倒装搭配.
for a moment/one moment.then do...
前一刻还...随后(下一刻)就.
eg:
for a moment the sun was shining,then came the pouring rain
前一刻还是艳阳高照,随后就是倾盆大雨
不过如果句子中间是句号的话,也可以不用倒装,原句只需要个主语就可以：
for a moment nothing happened.then the audience shouted together.