Fill in the following blanks with suitable words:
A tube-well draws underground water contained in an ............

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks us to fill in the blank in the sentence: "A tube-well draws underground water contained in an ............"

2. **Identifying Key Terms**: The key term here is "tube-well" and "underground water." We need to think about where underground water is stored.

3. **Defining Tube-well**: A tube-well is a structure created to access underground water. It typically consists of a long pipe that is drilled into the ground to reach water sources.

4. **Understanding Underground Water**: Underground water is stored in specific geological formations. These formations are crucial for supplying water to tube-wells.

5. **Finding the Right Term**: The geological formation that contains underground water is known as an "aquifer." An aquifer is a layer of rock or sediment that holds water and allows it to flow.

6. **Filling the Blank**: Therefore, the complete sentence is: "A tube-well draws underground water contained in an **aquifer**."

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