acidification

"He was a marine in World War II."

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

"The pencil's lead is made of carbon. "

"The chemistry experiment showed that carbon dioxide, a gas we exhale, contains two oxygen atoms for every carbon atom. "

"The atmosphere was thick with the smell of popcorn, as the kids gathered for the movie night. "

"The intricate making of the model airplane showcased the student's skill. "

"The factory's waste is acidifying the nearby river, harming the fish. "

"He threatened me with a knife."

"His rage only increased when I told him of the lost money."

"The tadpole changed into a frog.   Stock prices are constantly changing."

"The process of baking a cake involves several steps, from mixing the ingredients to putting it in the oven. "

"The absorption of new information during the lecture was crucial for passing the exam. "