e.g. The child was playing with a yo-yo while waiting for his friend.
e.g. Many people's relationship with food is a yo-yo, alternating between starving and overeating.
e.g. He was quite a yo-yo sometimes, and it was difficult to predict how he would behave in a situation.
e.g. They have a yo-yo relationship, going back and forth between hating each other and being very close.
e.g. Popular support for the candidate began to yo-yo based on her opinions on various issues.
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