first-grade

基本解释

Such protection zones shall be divided into first-grade protection zones and protection zones of other grades.
生活饮用水地表水源保护区分为一级保护区和其他等级保护区。
Certain water areas and land-based areas beyond the first-grade protection zones may be delineated as protection zones of other grades.
在生活饮用水地表水源一级保护区外，可以划定一定的水域和陆域为其他等级保护区。
A first-grade teacher was having trouble with one of her students.
一年级女教师跟她的一个学生较上了劲。

Now, seven months later, Taylor is beginning to read and does first-grade math.
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