Trachea are generally highly elastic but they may calcify with age. The trachealis muscle connects the ends of the incomplete rings and contracts during coughing, reducing the size of the lumen of the trachea to increase the rate of air flow. The esophagus lies posteriorly to the trachea, adjoining along the tracheoesophageal stripe. Circular horizontal bands of fibrous tissue called the annular ligaments of trachea join the tracheal rings together. The cartilaginous rings are incomplete to allow the trachea to collapse slightly so that food can pass down the esophagus. A flap-like epiglottis closes the opening to the larynx during swallowing
Less Commonly Taught Languages Less Commonly Taught Languages Less Commonly Taught Languages (or LCTLs) is a designation used in the United States for languages "other than" the most commonly taught foreign languages in US public schools. The term covers a wide array of world languages (other than English), ranging from some of the world's largest and most influential languages, such as Chinese, Russian, Arabic, Hindi, Portuguese, Japanese, Persian, and Turkish, to smaller regional languages studied in the US mainly by area experts, such as Twi, spoken in West Africa, and Finnish. The term arose out of a need to contrast the more commonly taught