Understanding the characteristics of that plant is very important for growing it.

It is difficult to solve this nonlinear equation.

This equation has nonlinear characteristics.

He is good at solving that equation.

He was holding my hand tightly.

He was running while holding a bag.

He always carries an umbrella around.

We conducted a spectral analysis to investigate the spectral characteristics of this substance.

I am learning how to solve differential equations.

Understanding chemical equations is difficult.