leading

"continuous firing leads the grooves of a rifle."

"leaded matter"

"The teacher is leading the class in a discussion about history. "

"The teacher was leading the class through the difficult math problem, explaining each step clearly. "

"The team is leading the competition in the school science fair. "

"to lead someone to a righteous cause"

"the path leads to the mill;  gambling leads to other vices"

"The shock led to a change in his behaviour."

"My grandmother is leading a quiet life now that she's retired. "

"Avoid leading questions if you really want the truth."

"He is a leading supplier of plumbing supplies in the county."

"The stock market can be a leading economic indicator."

"The leading of the class discussion was done by the student who volunteered first. "

"The document's leading was too tight; I needed to increase the leading to improve readability. "