It means that in setting life's goals many people do not try to go beyond their abilities and settle for average, meaning they set a reachable goal. If you set a higher goal for yourself, maybe you won't reach it, but it will motivate you to go beyond average, even if you miss the goal.
It means to have high expectations and high standards.
It means to set one's sights high.
work hard to achieve high!
It means it could shock you to death. Painful
There is a lot of danger there! What exactly do you mean? Danger to humans?
I think you mean dangerous. it means In danger (danger mean trouble or something like that/Peril)
danger
Electricity is transferred with high voltage and low current to reduce transmission loss ( I2R , where R= resistance of wire). As high voltage is present in transmission lines, Danger-high voltage is written.
It means to take away from danger. For example, you would want to remove a small child from danger.
danger
Danger.
it is in danger