faithful/ 'feɪθful /

1.adjective [+service] [ supporter] [ friend] 
(loyal) 忠实的

2.adjective [+husband] [ wife] [ lover] 
(sexually) 忠诚的

3.adjective [+account] [ version] [ copy] 
(accurate) 真实的

to be faithful to
 [+book,film] 忠实于
4.adjective [+husband] [ wife] 
(sexually) 忠诚于