根据短文内容理解，选择正确答案。    Hi, I'm Brian. This is the photo of my family. My grandfather is with glasses. He has little hair. The one standing next to him is my uncle. He is wearing a cap. My grandmother has gray hair. She is a kind woman. She is holding my younger brother. He has short curly hair. The woman standing behind me is my mom. She has straight brown hair. There is a little girl sitting on the table. Her name is Cathy. She is my sister. She is wearing a green T-shirt and a pair of green socks. It's her favorite color. Which one is my father? Well, he is wearing glasses, too. He is in brown shorts and brown shoes. His name is Sam. Now, do you know where he is?

两条直线相交成四个角，当其中一个角是直角时，其他三个角是____，这两条直线____，相交的这一点叫做____．

如图，已知AB=DC，若要用“SSS”判定△ABC≌△DCB，应添加条件是____  ．

已知f（x）是定义在﹣2，2上的奇函数，且f（2）=3．若对任意的m，n∈﹣2，2，m+n≠0，都有 $\frac{f\left(m\right)+f\left(n\right)}{m+n}$ ＞0．

写出带横线词的反义词。

油灯的光线暗。                            ____

在很暗的屋子里做手术很危险。            ____  

顿时，简易的“手术台”前一片光明。        ____