struggled

"The yoga instructor guided us through a series of back contortions to improve flexibility. "

"They are going to try climbing Mount Everest themselves."

"It is hard work to swim against the current."

"The siblings contended over which video game they would get to play next. "

"My brother constantly helps his younger sister with her homework, demonstrating his steadfast loyalty and support. "

"The difficulty of the math problem made it hard for many students to solve it. "

"It took a lot of effort to find a decent-sized, fully-furnished apartment within walking distance of the office.   He made a conscious effort to not appear affected by the stories in the paper."

"The ancient pyramids have stood for centuries, witnessing the rise and fall of civilizations. "

"The construction of the new school required a lot of labour from the workers. "

"Their diligent strive for better grades motivated them to study harder. "

"The toddler wobbled across the living room, giggling as she tried to reach her toys. "

"The stubborn jar lid wouldn't budge, despite my best twisting. "