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3. More than 800 silicate minerals are known, and they account for more than …
percent of Earth’s crust.
4. Some common nonsilicate mineral groups include …, …, … .
5. … include members that are major constituents in sediments and sedimentary
rocks.

Task 6. Find English equivalents for the following (see the text). Try to
build up your own sentences with them.
Розпочати вивчення мінералів; складати більшість гірських порід земної кори;
породоутворюючі мінерали; виробництво продукції; обопільно важлива група;
найбільш поширені елементи у земній корі; поєднуватись для того, щоб утворити
основний структурний блок; набагато менш розповсюджений; забезпечувати;
будівництво будинків (житла); проводити електрику; з’єднувати людей з
Інтернетом; осадові породи.

Task 7. Talk about the most important types of minerals: rock-forming,
economic, silicates and nonsilicates.

Task 8. Give a short summary of the text from Task 3.

Grammar focus
Modals in English

Task 1. Translate the sentences into Ukrainian paying special attention to
the underlined modals.
1. Data of this type led them to examine the possibility that magma might change
(evolve) and thus become the parent to a variety of igneous rocks.
2. Although the interiors of plates may experience some deformation, all major
interactions among individual plates (and therefore most deformation) occur along
their boundaries.
3. In addition, magma can originate far from plate boundaries.
4. It should be noted that not all minerals produce a streak when rubbed across a
streak plate.
5. Not all minerals have cleavage, but those that do can be identified by the relatively
6. smooth, flat surfaces that are produced when the mineral is broken.
7. However, colour should not be used to distinguish these groups.
8. Conversely, changing economic factors can turn a once profitable ore deposit into
an unprofitable deposit that can no longer be called an ore.
9. The Sierra Nevada batholith, for example, must be a continuous granitic structure
that forms much of the Sierra Nevada in California.

Task 2. Choose the best modal to complete the sentences and translate
them.
1. By definition, a plutonic body must/is to have a surface exposure greater than 100
square kilometers to be considered a batholith.
2. A 19th century study by G. K. Gilbert of the U.S. Geological Survey in the Henry
Mountains of Utah produced the first clear evidence that igneous intrusions can/
are able to lift the sedimentary strata they penetrate.
3. Not all pegmatites contain such large crystals, but these examples emphasize the
special conditions that must/have to exist during their formation.

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