The current is carried through metallic conductor by `………………………..` and in electrolytic substance by `…………………………` .

Explanation

To answer the question, we will break it down into two parts: the current carried through metallic conductors and the current carried through electrolytic substances.

### Step-by-Step Solution:

1. **Understanding Metallic Conductors**:
- In metallic conductors, the flow of electric current is primarily due to the movement of free electrons. Metals have a structure that allows electrons to move freely, which is why they are good conductors of electricity.

**Answer for the first part**: The current is carried through metallic conductors by **electrons**.

2. **Understanding Electrolytic Substances**:
- Electrolytic substances, when dissolved in water or melted, dissociate into ions. These ions are charged particles that can move and carry current. In an electrolyte solution, there are two types of ions: cations (positively charged) and anions (negatively charged).

**Answer for the second part**: The current is carried through electrolytic substances by **ions** (both cations and anions).

### Final Answer:
The current is carried through metallic conductors by **electrons** and in electrolytic substances by **ions**.

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