Sentence:  Miss Darcy was tall, and on a larger scale than Elizabeth; and, though little more than sixteen, her figure was formed, and her appearance womanly and graceful. She was less handsome than her brother; but there was sense and good humour in her face, and her manners were perfectly unassuming and gentle. Elizabeth, who had expected to find in her as <WSD>acute</WSD> and unembarrassed an observer as ever Mr. Darcy had been, was much relieved by discerning such different feelings. 
Meaning of the word marked with <WSD> tags:  Intense, sensitive, sharp.