Fill in the following black with suitable words :
Permanent teeth grow in place of _____ teeth.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question is asking for the type of teeth that are replaced by permanent teeth.

2. **Identifying the Types of Teeth**: Humans have two sets of teeth during their lifetime: milk teeth and permanent teeth.

3. **Defining Milk Teeth**: Milk teeth, also known as primary teeth, deciduous teeth, or baby teeth, are the first set of teeth that develop in children.

4. **Timing of Replacement**: Around the age of six, milk teeth begin to fall out to make space for the permanent teeth.

5. **Conclusion**: Therefore, the blank in the question can be filled with "milk" to indicate that permanent teeth grow in place of milk teeth.

**Final Answer**: Permanent teeth grow in place of **milk** teeth.

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