问题
选择题
Marry was holidaying with her family in a wildlife park______she was bitten on the leg by a lion.
A．while
B．when
C．before
D．after
答案
答案：B
考查be doing----when 句型，表示“正在做某事------突然” 。when在本句中为连词，相当于and just then,and just at that time,意为“就在这时”。引导一个突然出现的动作。句意：玛丽正和她的家人在野生动物园度假时，她被狮子咬伤了腿。