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combination of both, often separated by long periods of inactivity, eventually build the
cone-shaped structure we call a volcano.
Located at the summit of most volcanoes is a somewhat funnel-shaped
depression, called a crater (crater = a bowl). Volcanoes that are built primarily of
pyroclastic materials typically have craters that form by gradual accumulation of
volcanic debris on the surrounding rim. Other craters form during explosive eruptions as
the rapidly ejected particles erode the crater walls. Craters also form when the summit
area of a volcano collapses following an eruption. Some volcanoes have very large
circular depressions called calderas that have diameters greater than 1 km and in rare
cases can exceed 50 km.
During early stages of growth most volcanic discharges come from a central
summit vent. As a volcano matures, material also tends to be emitted from fissures that
develop along the flanks or at the base of the volcano. Continued activity from a flank
eruption may produce a small parasitic cone. Italy’s Mount Etna, for example, has more
than 200 secondary vents, some of which have built parasitic cones. Many of these
vents, however, emit only gases and are appropriately called fumaroles (fumus =
smoke).

Task 3. Answer the following questions, using the vocabulary from Task 1.
1. When does volcanic activity usually begin?
2. What is vent?
3. What is a volcano?
4. What is a crater?
5. How do craters form?
6. What are calderas?
7. Where do parasitic cones form?
8. What is a fumarole?

Task 4. Look at Figure 7.1 and try to describe the anatomy of a volcano.

Task 5. Find English equivalents for the following (see the text). Try to
build up your own sentences with them.
Початок вулканічної діяльності; збагачена газом магма; рухатись вверх
через розлом; завершитись отвором на поверхні; послідовні виверження лави;
довгі періоди бездіяльності; конічна структура; воронкоподібна западина;
поступове накопичення вулканічних уламків; частинки, які швидко вивергаються;
ранні стадії формування вулкану; тріщини, які утворюються з боків вулкану;
побічні (другорядні) вихідні отвори.

Task 6. Give a short summary of the text from Task 2.

Grammar focus
The Present Indefinite versus the Future Indefinite tenses in complex
sentences

Task 1. Read the following sentences, translate them into Ukrainian. Pay
attention to the forms of the verbs in the Present and the Future Indefinite tenses.
1. If this activity is sustained, it will eventually build a chain of volcanic structures
that emerge from the sea as a volcanic island arc.
2. If spreading continues in this region, the African plate will split into two plates,
separated by a new ocean basin.

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