“入学人数”常见的英文表达是 “enrollment figure” 或 “number of students enrolled” 。
enrollment figure：较为简洁正式，常用于统计数据、教育报告等场景。例如：The enrollment figure for this year's freshmen is higher than expected.（今年新生的入学人数高于预期。）
number of students enrolled：表达更为直观清晰，强调已注册入学的学生数量。例如：We need to know the exact number of students enrolled in each course.（我们需要知道每门课程确切的入学人数。 ）