Focus on Vocabulary:

• sonar - гідролокатор
• sea floor - морське дно
• unexplored frontier - незвідана (недосліджена) зона, територія, ділянка
• impenetrable - impenetrable, до якого неможливо дістатися
• ocean layer - шар океану
• submerged - занурений
• featureless - невиразний, позбавлений особливостей

Adjectives

• used for descriptions
• come before nouns

NB Mind the order of adjectives if you use more than one.
1. Determiner (articles, numbers, amount, owner): a/an, the, many, some, etc
2. Observation (opinion) - quality of the noun: useful, cheap, urgly
3. physical description (Size, Age, Shape, Colour): tiny/modern/flat/blue
4. Origin: Thai
5. Material: copper, plastic
6. Qualifier: wedding
7. Noun

e.g.:
Lily's useful square wooden box.

nouns + to be + adjectives (as complements) - when the phrase becomes a full sentence

• phrase - the big, red, plastic car
• sentence - The car is big, red and plastic.

Adjectives to describe shape: circular, triangular, rectangular, spherical, square, egg-shaped, kidney-shaped

When the amount is not exact you can say:

• approximately (formal way)
• about ..
• around ...
• around about
• ...or so

Focus on the Topic

We know more about the surface of the Moon, of the surface of Mars than we do about the sea floor. The sea floor remains the last unexplored frontier. This is because it's covered by this impenetrable ocean layer that we can't see through. The only way we can see the sea floor is using sonar. The largest reef they mapped is about 10 or so km across. It's an ovel-shaped feature, so it covers around one hundred km2. Because of the fact that they are submerged in 30 metres or so of water, the reefs are very hard to see. No one had realised that the gulf contained reefs just like the Great Barrier Reef. The Gulf of Carpentaria is very flat and featureless.