Exercise 4 вставьте артикли, где это необходимо:

1. … tooth consists of a crown and one or more roots. … crown is …visible part, … root is … hidden part.
2. … tooth is composed of enamel, dentine, cementum and pulp.
3. enamel is … hardest substance in the body.
4. cementum is … outer covering of …root.
5. dentine occupies … interior of the crown and root.
6. … vessels and … nerves of the pulp enter … root apex through the apical foramen.
7. … space occupied by the pulp is called … pulp chamber.

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8. every tooth is inserted into … jaw by its roots.
9. … part of the jaw containing the teeth is known as the alveolar process.
10. it is covered with … soft tissue called gum.
11. … tooth is attached to its socket in the jaw by … soft tissue called the periodontal membrane.

1. A tooth consists of a crown and one or more roots. The crown is the visible part, while the root is the hidden part.
→ Explanation: "A tooth" is a general reference, so we use the indefinite article "a" before it. "The crown" and "the root" refer to specific parts, so we use the definite article "the" before them.

2. A tooth is composed of enamel, dentine, cementum, and pulp.
→ Explanation: Same as the previous question, "a tooth" is a general reference, so we use the indefinite article "a" before it.

3. Enamel is the hardest substance in the body.
→ Explanation: "Enamel" is a specific substance, so we use the definite article "the" before it.

4. Cementum is the outer covering of the root.
→ Explanation: "Cementum" is a specific substance, so we use the definite article "the" before it. The word "root" is also specific in this context, so we use the definite article "the" before it.

5. Dentine occupies the interior of the crown and root.
→ Explanation: "Dentine" is a specific substance, so we use the definite article "the" before it. The words "crown" and "root" are also specific in this context, so we use the definite article "the" before them.

6. The vessels and the nerves of the pulp enter the root apex through the apical foramen.
→ Explanation: "The vessels" and "the nerves" refer to specific entities, so we use the definite article "the" before them. "The pulp" refers to a specific part, so we use the definite article "the" before it. "The root apex" and "the apical foramen" are also specific in this context, so we use the definite article "the" before them.

7. The space occupied by the pulp is called the pulp chamber.
→ Explanation: "The space" refers to a specific place, so we use the definite article "the" before it. "The pulp" and "the pulp chamber" are also specific in this context, so we use the definite article "the" before them.

8. Every tooth is inserted into the jaw by its roots.
→ Explanation: "Every tooth" refers to individual teeth in a general sense, so we use the indefinite article "every" before it. "The jaw" is a specific part, so we use the definite article "the" before it.

9. The part of the jaw containing the teeth is known as the alveolar process.
→ Explanation: "The part" and "the jaw" refer to specific entities, so we use the definite article "the" before them. "The teeth" and "the alveolar process" are also specific in this context, so we use the definite article "the" before them.

10. It is covered with soft tissue called gum.
→ Explanation: "Soft tissue" is a general reference, so we use the indefinite article "soft" before it. "Gum" refers to a specific type of tissue, so we use the definite article "the" before it.

11. A tooth is attached to its socket in the jaw by soft tissue called the periodontal membrane.
→ Explanation: Same as question 10, "a tooth" is a general reference, so we use the indefinite article "a" before it. "The socket," "the jaw," and "the periodontal membrane" are specific in this context, so we use the definite article "the" before them.