sudden

"The Amazon rainforest is home to a vast variety of plants and animals because it rains almost every day. "

"It surprises me that I owe twice as much as I thought I did."

"Let me tell you how it happened."

"it precipitated their success"

"a horse that startles easily"

"He raised his hand to make his announcement and said "Excuse me everyone, I have an announcement to make."

"Be sure to finish your homework before you go to bed!"

"The heavy rain was unexpected; we had planned a picnic in the park. "

"It was a surprise to find out I owed twice as much as I thought I did."

"The temperature in the room dropped nearly 20 degrees; it went from hot to cold."

"The frequent occurrence of noisy construction near my house has made it hard to concentrate on my studies. "

"The presentation about the new school rules was very clear and easy to understand. "