extremely surprising or difficult to understand
The size of the universe is truly mind-boggling.
It is mind-boggling to think how the ancient Egyptians built the pyramids without modern technology.
to guess or form ideas about something without having complete information
Scientists speculate that there may be water on Mars.
She speculated about why her friend didn’t answer the phone.
coming from or existing outside Earth
Many people wonder if extraterrestrial life really exists.
Some believe that extraterrestrial beings helped build the pyramids.
to control and use something, especially natural resources or energy
Ancient Egyptians harnessed the power of the Nile River for farming.
The scientist harnessed solar energy to power the device.
the resistance that occurs when one surface rubs against another
Rubbing your hands together creates friction and warmth.
The engineers reduced friction between the machine parts to make it work more smoothly.
the ability to think of new and clever ideas or solutions
The invention showed the scientist’s great ingenuity.
With ingenuity, the workers built a bridge using only simple tools.
