Final answer:
Friar Lawrence's special skill is his extensive knowledge of herbs and their medicinal uses, which plays a key role in the plot of Shakespeare's 'Romeo and Juliet'.
Step-by-step explanation:
Friar Lawrence, a character in Shakespeare's play Romeo and Juliet, is well-known for his special skill in the area of herbal knowledge and the use of plants for medicinal purposes. His expertise extends to the understanding of how plants and herbs can affect the human body and mind, which he applies throughout the play in various situations, such as creating the potion that Juliet takes to appear dead. This knowledge of plants and herbs is significant within the context of the play, as it influences the progression of the plot and the fate of the characters.