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"My dad installed a new security system in our house yesterday. "

"The old plumber worked with lead pipes in the school's plumbing system. "

"My brother's opinion is the opposite of mine on the best way to study for the exam. "

"The dry-stone wall used a large, flat through to support the top stones. "

"The screen protector acted as a preventer, stopping the phone's glass from cracking when it fell. "

"The water in the swimming pool is a fluid that easily takes the shape of the pool. "

"He intends to go to university."

"Keep going in the same direction."

"The carpenter used a T-square to draw a normal to the edge of the wooden board. "

"By now, you must surely know which is which."

"The children dirty their hands while playing in the mud. "

"The lightning caused thunder."