初三学生豆豆最近心理很苦恼，找到心理咨询师倾诉：“父母‘望子成龙、望女成风’心切，而我的学习成绩不是很好，但已经尽力了。所以我对父母的对抗心理特别严重，经常冲父母发脾气，顶撞父母，我该怎么办呢？”如果你是心理咨询师，你会告诉他（    ）

①理解父母的期望       ②继续与父母对抗

③尊重父母的关爱       ④主动与父母沟通交流

—Yes,      .

    Hello! Nice to meet you. Now let me introduce myself (自我介绍) to you. My name is Mary. I'm 12 years old. I'm from Canada and I speak English. I'm a tall girl. I have long brown hair and big blue eyes. I like music a lot. I often sing songs with my friends in my free time. I have a happy family. There are four people in my family. They are my mom, my dad, my sister and me. I like China very much and I want to visit Beijing, but I can't speak Chinese at all.

    I hope (希望) to be your friend, then we can help each other with English and Chinese.

根据材料内容，选择最佳答案。

若x，y满足约束条件 $\{\begin{array}{c}x-y\ge 0\\ x+y-2\le 0\\ y\ge 0\end{array}$ ，则z=3x﹣4y的最小值为____