Exercise 4. Read and translate the text:

The structure of the oral cavity

The first section of the mouth is known as the oral cavity, or the mouth cavity. This space is bordered in the front and to the sides by the two alveolar arches, which contain the teeth.

The teeth are a group of hard organs found in the oral cavity. Teeth are used to masticate (or chew) food into tiny pieces. They also provide shape to the mouth and face and are important components in producing speech.

A tooth can be divided into two main parts: the crown and root. Found above the gum line, the crown is the enlarged region of the tooth involved in chewing. Below the gum line is the region of the tooth called the root, which anchors the tooth into a bony socket known as an alveolus. The narrowed part of a tooth between the crown and the root is called a neck. Each tooth is an organ consisting of three layers: the pulp, dentin and enamel.

The lips and cheeks contain the mimetic muscles: they are covered externally with the skin, and lined in the vestibule with the mucous membrane. The mucous membrane on the alveolar processes the jaw closely adheres to the periosteum and is called the gums (gingivae). Gingiva is the soft tissue that covers and protects the root of the tooth. The gum is not attached to the tooth. A red, moist, glistening tissue, which is called the mucous membrane or mucosa forms a protective covering for the tongue, palate, floor of the mouth and the inside of the lips and cheeks, much as the skin does for the rest of the body.

The tongue is a muscular organ covered with a mucous membrane. It consists of the tip, body and base. Underneath the tongue and the inner surface of the cheeks there are glands, three principal pairs being recognized: the sublingual, submandibular and parotid. One pair of glands, the parotid, is located in front of the ears. Another pair, submandibular, is situated under the lower jaw. The third pair of glands is under the tongue and is known as the sublingual. They supply water, ferments and mucus to the food which is ground up by the teeth. Numerous small glands (labial, buccal, palatine and lingual) help producing saliva. Moreover, there are three pairs of large salivary glands whose ducts also open into the oral cavity. The secretion of the salivary glands is called saliva. Saliva breaks down starches that is the first step in digestion.

Exercise 5. Answer the questions to the text:

What are the names of the principal glands of the oral cavity?

What is the tongue fastened to?

What do the salivary glands secrete?

What does the alveolar arch contain?

What is the function of the teeth?

What parts can a tooth be divided into?

What layers does the tooth consist of?

What is gingiva?

What is the function of the mucus membrane?

Exercise 6.Match the following Ukrainian word combinations with the English ones:

1. alveolar arch	1. піднижньощелепна та привушна залози
2. the crown and root	2. жувати їжу на маленькі шматочки
3. to anchor the tooth	3. формувати захисне покриття
4. to be lined with the mucous membrane	4. коронка та корінь
5. submandibular and parotid glands	5. альвеолярна дуга
6. secretion of the salivary glands	6. прикріплятися до надкісниці
7. to form a protective covering	7. закріплювати зуб
8. to masticate food into pieces	8. виділення слинних залоз
9. to adhere to the periosteum	9. вистилатися слизовою оболонкою