Under what circumstances does such a quantity have a definite value?

下这样一个量会具有一个确定的值呢？

Conclusion MRI has very definite value in diagnosing diffuse astrocytoma.

结论MRI对弥漫性星形细胞瘤的诊断具有十分重要的价值。

It has a definite value for raising the accuracy of triangulation in mountain area.

对提高山区三角高程测量的精度有一定的实用价值。

Memory and regular study have definite value and it always helps you in leading a life.

记忆和不断的学习无疑最具有价值，他能主导你的生活。

Combination analysis of methylation status in SFRP genes may has definite value on estimating prognosis of ESCC.

联合检测SFRP基因家族甲基化状态对于食管癌的预后判断有一定指导意义。