"he did it on a bet"
"I bet she will be there!"
"I bet $100 on that new horse"
"She played all her money on the dark horse"
"you can count on me to help you any time"
"Look to your friends for support"
"You can bet on that!"
"Depend on your family in times of crisis"
It's foolish to bet on horses.
赌马是愚蠢的。
bet sb sth on sth/v-ingI'll bet you anything on it.
对那件事我敢跟你赌任何东西。
He bet me ten dollars on John's coming.
他跟我打赌十美元说约翰会来。
I bet you two cents on his winning.
我跟你打赌2美分他赢。