These two lines coincide with each other.

这两条线相重合。

Observational studyaims at the approach to a dynamic system whose equation is undeterminable.

该方程组的解有限时段上的采样值序列重合。

Pectose exists in the fleshy pulp of unripe fruit;during the process of ripening it changes to pectin;by cooking, pectin is changed to pectosic acid, and by longer cooking to pectic acid.

重合果胶存于未成熟果的肉浆中，成熟过程中它变成胶质，时胶质变成重合果胶酸。