单项选择题 "Look at those pretty girls’ skirts" is______, because it is not clear whether the girls or the shirts are "pretty" .(2011-71)

单项选择题 The crowd went______as soon as the singer stepped onto the stage.(2011-67)

单项选择题 When Linda heard the good news she tried to sound casual, but her excitement was obvious. The underlined part means（）