Questions about example sentences with, and the definition and usage of "Specialists"

A: "To err is human to forgive divine" implies not only to the specialists but also to the experts in letter and spirit.

A: × Specialists of North Korea say the regime will collapse and this regime will the last dictate regime
✓ Specialists of North Korea say the regime will collapse and will be the last dictating regime.

× Many North korean escaped to South Korea
✓ Many in North Korea escaped to South Korea.

× North Korea keeps sending to trash bolloons to South Korea.
✓ North Korea keeps sending trash balloons to South Korea.

× I think they need any help, so they try to get attraction
✓ I think they need help, so they're trying to attract attention.

A: × Specialists estimate that by the end of the day the level of water will be around 2 meters.
✓ Experts estimate that by the end of the day, the level of water will be around 2 meters.

× Should I use the "assess" instead of the "estimate"?
✓ Should I use the "assess" instead of the "estimate"? = no

In general, an estimate happens BEFORE the event; a assessment happens AFTER the water rises.
Experts estimate/predict that by the end of the day, the water level will be around 2 meters.
At the end of the day, the amount of water in the river was assessed at 2 meters.

A: Specialists are not necessarily educated people because truly educated people know various things. Whether you are educated or not, it doesn't depend on how well you know one thing.

Logically, the second sentence doesn’t make much sense.

A: "a rare"

A: The second one is perfect.