（ ）21. The audience waited until the curtain rose and then_____ laughter at the sight of the funny actor.
A. burst out B. burst into C. broken into D. began with
（ ）22.“After World War Ⅱ,many of the cities across western European countries_____ , ”our guide said.
A. lied in ruin B. lay in ruins C. lay in ruin D. lying in ruins
