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Level C1 ⏱️ 20 Minutes

Deep-Sea Exploration & Mining

Learn ten words about the deep sea and practise saying them out loud.

📌 How to use this lesson

👨‍🏫 For Teachers

Guide students through this 20-minute vocabulary and speech training module in sequence.

Monitor practice answers using automated checks and assist during the shadowing recording tasks.

👩‍🎓 For Learners

First, study the 10 target words, collocations, and memory tips in the word table.

Next, complete the 16 practice activities and end by recording your voice in the shadowing section.

Word table

Study the 10 target vocabulary words below, divided into 3 theme groups.

🌊 Theme 1: The Ocean Floor

Word	Meaning	Common Collocations	Example Sentence	Memory Tip
seabed	The ocean floor underneath the water.	map the seabed, deep seabed	Robotic cameras explored the dark seabed.	Picture "sea" + "bed": the bed where the ocean rests.
trench	A long, deep, narrow valley in the ocean floor.	ocean trench, deep trench	The vessel reached the edge of the deep trench.	Think of a deep trench coat pocket going straight down.
sediment	Soft solid matter that settles at the ocean bottom.	thick sediment, sediment layer	Thick sediment covered the ancient rocks.	"Settle" sounds like "sediment": mud settling down.
uncharted	Not mapped, surveyed, or recorded on maps.	uncharted waters, uncharted area	The submarine entered uncharted waters.	"Un" (not) + "chart" (map) = not on any map.

🛠️ Theme 2: Equipment

Word	Meaning	Common Collocations	Example Sentence	Memory Tip
submersible	A small vehicle designed to operate under water.	manned submersible, deploy submersible	Scientists sent a submersible into the deep water.	"Sub" (under) + "merge" = craft that goes under water.
sonar	System using sound waves to find objects under water.	sonar system, sonar signal	The ship used sonar to measure water depth.	SOund Navigation And Ranging: sound bouncing back.
vessel	A large ship or boat for deep sea ocean travel.	research vessel, ocean vessel	The research vessel sailed across the ocean.	A vessel holds liquid or passengers, like a large ship.

💎 Theme 3: Resources

Word	Meaning	Common Collocations	Example Sentence	Memory Tip
mineral	Valuable natural solid substance found in rocks.	mineral deposits, rich in minerals	Deep ocean rocks contain rich mineral deposits.	"Mine" is in "mineral": natural wealth dug from the Earth.
ore	Rock or earth containing valuable metal inside.	extract ore, rich ore	Submarines collected valuable iron ore samples.	"Ore" rhymes with "more": rock holding more metal.
mining	Process of extracting valuable minerals from earth.	seabed mining, ocean mining	Environmentalists study the impact of seabed mining.	"Mine" + "-ing": the action of digging up minerals.

Practice

Complete these 16 items from easy to hard to test your understanding.

💡 Pattern example: "Such was the strength of the current that the vessel turned back."

Part 1: Collocation Matrix (Match Verbs to Nouns)

Match each verb on the left with its most natural oceanography noun column.

Verb

sonar

ore

seabed

submersible

1. Map

____sonar ____ore ____seabed ____submersible

2. Pilot

____sonar ____ore ____seabed ____submersible

3. Extract

____sonar ____ore ____seabed ____submersible

4. Emit

____sonar ____ore ____seabed ____submersible

Part 2: Gap-Fill Sentences

Word Bank

uncharted mineral submersible sediment

5. The ocean floor was dark, but the crew guided the ____ toward the research site.

6. Thick layers of ____ covered the ancient rock formations.

7. Researchers discovered valuable ____ deposits near the thermal ridge.

8. The expedition team prepared to cross an ____ section of the Pacific Ocean.

Part 3: Choose the Word

Select the word that correctly completes the context of each sentence.

9. The expedition ship dropped anchor directly above the deepest ocean ___.

____ a. trench ____ b. vessel ____ c. sonar

10. Engineers used high-frequency ___ signals to measure the distance to the seafloor.

____ a. mineral ____ b. sonar ____ c. sediment

11. The large research ___ carried twenty scientists across the Atlantic Ocean.

____ a. vessel ____ b. trench ____ c. ore

12. Companies are investing in deep-sea ___ to collect rare seabed metals.

____ a. sonar ____ b. mining ____ c. sediment

Part 4: Sentence-Building

Rearrange the given words into a correct natural sentence.

13. Words: [ mapped / trench / the / crew / The ]

Type the complete sentence below:

____

14. Words: [ sediment / ocean / covered / Thick / the ]

Type the complete sentence below:

____

15. Words: [ vessel / entered / waters / uncharted / The ]

Type the complete sentence below:

____

16. Words: [ produced / Seabed / rich / ore / mining ]

Type the complete sentence below:

____

Shadowing

Listen to each item using the audio button, then record your voice to match the stress and rhythm.

Part 1: Key Collocations (Items 17–20)

Item 17: Collocation

map the deep seabed

[Bài tập luyện nói]

____

Item 18: Collocation

ocean trench exploration

[Bài tập luyện nói]

____

Item 19: Collocation

thick layers of sediment

[Bài tập luyện nói]

____

Item 20: Collocation

uncharted underwater territory

[Bài tập luyện nói]

____

Part 2: Sentences (Items 21–24)

Item 21: Sentence

The crew mapped the dark ocean floor with new sonar equipment.

[Bài tập luyện nói]

____

Item 22: Sentence

Such was the strength of the current that the vessel turned back.

[Bài tập luyện nói]

____

Item 23: Sentence

Scientists sent a submersible down into the deep trench.

[Bài tập luyện nói]

____

Item 24: Sentence

Thick sediment covered the rocks at the bottom of the sea.

[Bài tập luyện nói]

____

Part 3: Advanced Sentences (Items 25–26)

Item 25: Sentence

Deep ocean mining requires high technology and careful planning.

[Bài tập luyện nói]

____

Item 26: Sentence

The team discovered rich mineral ore in uncharted waters.

[Bài tập luyện nói]

____

Part 4: Single Word Focus (Items 27–28)

Item 27: Focus Word

seabed

[Bài tập luyện nói]

____

Item 28: Focus Word

sediment

[Bài tập luyện nói]

____

Deep-Sea Exploration: Vocabulary and Pronunciation

Deep-Sea Exploration & Mining

📌 How to use this lesson

Word table

Practice

Part 1: Collocation Matrix (Match Verbs to Nouns)

Part 2: Gap-Fill Sentences

Part 3: Choose the Word

Part 4: Sentence-Building

Shadowing

Part 1: Key Collocations (Items 17–20)

Part 2: Sentences (Items 21–24)

Part 3: Advanced Sentences (Items 25–26)

Part 4: Single Word Focus (Items 27–28)

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