小华同学性格内向孤僻，很少主动与他人交往。他每天除了上课很少与其他同学交往。他的这种性格（    ）

①会影响自己的身心健康                        ②会影响正常的学习生活

③会影响个人今后的发展                        ④是个性强的突出表现

“雷贝拉唑钠肠溶片”是治疗胃病的一种药．下面为该药说明书上的部分信息：

【主要成分】雷贝拉唑钠，化学式：C₁₈H₂₀N₃O₃SNa

【用法用量】成人每日口服1次10毫克，根据病情也可每日口服1次20毫克．

【药物实验】健康成年男子分别在空腹情况下或饭后口服本药20毫克，血浆中药物浓度随时间的变化情况如图所示．

结合上述信息，回答下列问题：

有如下几个结论：
①相关指数$R^2$越大，说明残差平方和越小，模型的拟合效果越好；
②回归直线方程：$\stackrel{\wedge }{y}=bx+a$一定过样本点的中心$\left(\stackrel{-}{x},\stackrel{-}{y}\right)$；
③残差点比较均匀地落在水平的带状区域中，说明选用的模型比较合适；
④在独立性检验中，若公式$K^2=\frac{n{\left(ad-bc\right)}^2}{\left(a+b\right)\left(c+d\right)\left(a+c\right)\left(b\left|+d\right|\right)}$中的|ad-bc|的值越大，说明“两个分类变量有关系”的可能性越强.
其中正确结论的个数有（   ）个.  

阅读理解

    Hi, I'm Mo Hongwei from Changsha, Hunan. I'm going to enjoy myself during the New Year holiday. On 1st January, I'm going to stay at home and do my homework. On the morning of 2nd January, I'm going to meet my grandfather's friend Mr. Smith at the train station. In the afternoon, I'm going to take Mr. Smith around my school. In the evening, we're going to have a welcome party for him. On the morning of 3rd January, I'm going to ask Mr. Smith to teach me to write with the left hand. And I'm going to ask him to give me some advice(建议) about reading. I think my New Year holiday is going to be fun.