I am expecting a Skype call between 7 pm and 8 pm tonight, please remind me 30 minutes before.
[IN:CREATE_REMINDER I am [SL:TODO [IN:GET_TODO [SL:TODO expecting a Skype call ] [SL:DATE_TIME between 7 pm and 8 pm tonight ] ] ] , please remind [SL:PERSON_REMINDED me ] [SL:DATE_TIME 30 minutes before ] . ]