学校里不同年级的学生一起在田里劳动。

Students of various grades at the school worked together in the fields.

不同年级的学生都很努力学习。

The students in different grades all study hard.

其次要加强与同一学科不同年级或同一年级不同学科教师间的交流与合作，以提高教学质量；

Next, the same subject different grades teachers and the same grade different subjects teachers should communicate and cooperate closely to enhance the teaching quality.

目的了解学习素质在不同年级、不同性别的差异性。

Objective Understanding the differences of study diathesis in different grades and gender.

不同年级、年龄学员的学习态度没有差别；

The undergraduates of different grades had not different study attitudes, neither did the undergraduates of different ages.

不同性别、不同校区、不同年级的学生心理反应存在显著差异。

Results There were some differences on segregated-or-no factor, on gender, on campus areas, and grades.

不同年级学生所掌握的艾滋病知识差异有显著性。

The differences of AIDS related knowledge were significantly among the students in different grades.

不同年级的学生及各类学校的学生都使用教科书。

Students at all levels and in all kinds of schools use textbooks.

不同年级、不同专业的女大学生需要的心理辅导内容差异显著；

Third, there is great difference in the need of psychological guidance for female college students in different grades or different majors;

初中与高中不同年级学生的学习适应性水平有差别。

Difference also exists in different grade students adaptation to learning.