He couldn't come up with an answer.
他答不上来.
He couldn't come up with an appropriate answer just at the time.
那时他想不出一个合适的答案.
请用come up with造句
He couldn't come up with an answer.
他答不上来.
He couldn't come up with an appropriate answer just at the time.
那时他想不出一个合适的答案.