undulating

"Clouds were forming interesting shapes in the sky. "

"to curve a line"

"The gentle motions of the swing lulled the baby to sleep. "

"The dog seemed happy, seemingly wagging its tail excitedly. "

"The magician made a rabbit disappear from his hat, amazing all the children. "

"The gentle undulation of the wheat field in the breeze was mesmerizing. "

"The twins resemble each other."

"The waiter carried the trays of food smoothly, avoiding any spills. "

"Last summer, my family traveled to Italy for vacation. "

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

"Using artificial additives, scientists can create the illusion of fruit flavours in food."

"The apple is falling from the tree. "