中国大学MOOC: He came to warn him of the ________(danger; dangers) ahead.
                    举一反三
- He came to warn him of the ________(danger dangers) ahead
 - Though __________ (warn) of the danger, he still went skating on the thin ice.
 - 中国大学MOOC: We came to his ______ and pulled him out of the river.
 - 9. He was an extraordinary man of courage. So when danger came, he would never ________.
 - 中国大学MOOC: When he came in, we _____ the problem.
 
