semicircle

"The recipe calls for a precise measure of baking soda. "

"The violinist was a master of her instrument."

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

"a stone cutter; a die cutter"

"This flow chart represents the assignment of tasks in our committee."

"My son is learning about geometry in his math class, studying how shapes relate to each other in space. "

"The construction paper shape was a triangle. "

"He is a student of life."

"The perfect tense, used to describe actions completed before another time, is a useful grammatical tool. "

"The set of all points (x, y) such that (x − 1)2 + y2 = r2 is a circle of radius r around the point (1, 0)."

"I solved all of the acrosses, but then got stuck on 3 down."

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