optic

"The image was magnified by a factor of eight."

"The student used a microscope to see the tiny cells in the plant leaf. "

"The violinist was a master of her instrument."

"It took him only twenty minutes to perform the task."

"He listened carefully to his mother's concerns, feeling sorrowful about her disappointment. "

"The violinist was a master of her instrument."

"We measured the temperature with a thermometer.   You should measure the angle with a spirit level."

"The bartender mixed a colorful cocktail for the customer at the busy bar. "

"After years of struggling with addiction, he finally admitted he was an alcoholic and sought help. "

"The teacher wrote the math problem on the blackboard. "

"The students in the group interact well during their project, sharing ideas and helping each other. "

"Would it bother you if I smoked?"