He is an expert in pharmacognosy, and has a deep knowledge about the medicinal value of plants.

He is a specialist in that field.

This medicinal shampoo helps maintain scalp health.

He is majoring in botany at university.

His eyes are a deep blue.

This herbal medicine helps to alleviate the symptoms of a cold.

My grandmother always believes in natural remedies and chooses natural treatments.

Your opinion has great value.

I'm always amazed by his extensive knowledge.

His specialty is physics.