题目

The teacher stressed again that the students should not _____ any important details while retelling the story. A . bring out B . leave out C . let out D . make out 答案：B将三个分别标有A，B，C的小球随机地放入编号分别为1，2，3，4的四个盒子中，则第1号盒子内有球的不同放法的总数为（ ）A．27B．37C．64D．81