stay calm,in case,to one's surprise,play the role of,dream of,on duty,get into trouble,be stuck in
should,may,used to,need,mustn't
①He was stuck in a foreign country and .(have 短语)
②He was stuck in a foreign country .(with 短语)
① ,we all decided to organize a concert for the festival.(介词短语)
②,we all decided to organize a concert for the festival.(副词)
① They went to the concert .(状语从句)
②They went to the concert .(介词+ doing)
→ (what 引导的主语从句)
→(dream of doing)