①附中高一年级聪明的学生；

②直角坐标系中横、纵坐标相等的点；

③不小于3的正整数；

④$\sqrt{3}$的近似值；

考察以上能组成一个集合的是____ 

I can play         chess but I can't play           guitar.

通过植物组织培养的方法，快速繁殖花卉，利用的原理是

画出下列句中的错别字并改正在后面的横线上内。

（1）暗狐外面还镶有明显的亮狐。                             ____ 

（2）随着太阳的缀落，紫光下移。                         ____ 

（3）最令人迷获的幻觉，是日落时的太阳看上去要比高挂天空时大两倍半到三倍半。____                    

阅读短文，选择正确的答案。
    Tom went to Beijing by plane on his holiday. Every day he had fun with his parents. They went boating. They saw some elephants. They went swimming. They ate lots of delicious food. They also took many beautiful pictures. They will come back tomorrow. He enjoys his holiday.