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"The teacher required the students to bring their textbooks to class every day. "

"He is a student of life."

"My friend told me there was something in the box, but I didn't know what it was yet. "

"Attending the mandatory safety training is a compulsory requirement for all new employees. "

"The amount of time it takes to finish my homework is a variable; sometimes it takes me an hour, other times it takes much longer. "

"My sister is very helpful, especially when it comes to organizing things. "

"My sometimes neighbor, a retired teacher, still visits the school occasionally. "

"In German, all nouns are capitalized."

"He programmed the DVR to record his favorite show."

"Deaf and mute people communicate using languages like ASL."

"Professor Davies, a noted academic, explained the philosophical ideas of Plato to her students. "

"To see how much sunlight a plant needs, the amount of water given to each plant was a parameter that was kept constant. "