The answer to your question:
Self-Assured.
Answer:
It is the period in which people first used metals on a regular basis to manufacture weapons and tools.
Explanation:
Maybe nothing really is perfect
The sentence active is: I keep the mayonnaise in the refrigerator.
The sentence passive is: The mayonnaise is kept in the refrigerator (same thing as the question)
If the subject is performing the action, then the sentence is in an active voice. However, if the subject is simply receiving the action, then the sentence is in a passive voice. A helpful tip is to add "by zombies" after the verb. It helps a ton. If you can insert "by zombies" after the verb then it is passive.
Explanation:
1. Peter didn't break that bottle
2. They are not learning English in the room.
3. Something changed my mind.
4. Some one had told me about it.
5. I know her telephone number.
6. My students will not bring the children home.
7. They did not send me a present last week.
8. She didn't give us more information
9 The chief engineer wasn't instructing all the workers of the plan.
10 They can make tea with cold water.
I think that's right !!!