front lines is front line's Plural Form

front line

US 
UK 
  • na.第一线
  • Web前线;前沿阵地
Plural Form:front lines  
na.
1.
前线,第一线

Sample Sentence

Definition:
Category:AllAll,OralOral,WrittenWritten,TitleTitle,TechnicalTechnical
Source:AllAll,DictionaryDictionary,WebWeb
Difficulty:AllAll,EasyEasy,MiddleMiddle,HardHard