oscillated

"My need to sleep early is conflicting with my desire to finish this interesting book. "

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

"The seamstress used a sturdy between to create a precise, even stitch on the thick upholstery fabric. "

"I stopped at the traffic lights."

"The student began to vacillate between choosing the easy math problem or the challenging one, unsure which would be the best use of her time. "

"Dance to the rhythm of the music."

"A pendulum oscillates slower as it gets longer."

"The new desk is longer than the old one, so I have more space to work. "

"My friends and I have different opinions about which restaurant to go to for dinner. "

"The grandfather clock in the hallway has a pendulum that swings back and forth, keeping perfect time. "

"The sergeant major is a regular in the British Army. "

"a slow train;  a slow computer"