be worthy to be done = be worthy ofbeing done It’s worthwhile to do sth = it’s worthwhile doing sth “疑问词+ to do” 结构，在句中做主语、宾语、表语 How to do it is a question. I don’t know what to do next. it 做形式主语 It has been proved that pride goesbefore a fall. 事实证明骄必败。 what 引导主语从句，在从句中作主语 What he has said is of great importance.What happened to him remained unknown.
