I was afraid to __serve___ my customers because I was afraid __of___ them.
be afraid to do sth 害怕去做某事
be afraid of + n/动名词 害怕,担忧某物/某事
I was afraid to __serve___ my customers because I was afraid __of___ them.
be afraid to do sth 害怕去做某事
be afraid of + n/动名词 害怕,担忧某物/某事