A～F是初中化学的常见物质，A与B的组成元素相同，D、E在通常状况下是气体，F是大理石的主要成分。其转化关系如下图所示，部分反应物、生成物和反应条件未标出。

Lili was ______ holiday in Shanghai. （  ）

动点A从原点出发向数轴负方向运动，同时，动点B也从原点出发向数轴正方向运动，3秒后，两点相距15个单位长度．已知动点A，B的速度比是1：4．（速度单位：单位长度/秒）

用所给动词的正确形式填空。
    Be sure ____ (go) to this exhibition at the Sunshine Gallery. Ms. Wang ____ (consider) to be one of the best known Chinese photographers in the world today, and some of her most famous photos are in this exhibition. Ms. Wang ____ (get) to Sunshine Town yesterday afternoon. She really____ (have) something for everyone.  There are many great photos of the countryside. Maybe you ____ (see) some of them on TV before.  It's quite different when you see the real photos. Whatever you do, ____ (not miss) this exhibition!

切除胸腺的幼年小鼠，其免疫功能表现为