Please observe below Naming Pattern:

Noun + Relative clause (= Postmodifier: Relative pronoun, used as Adverbial element)

Utter below naming pattern reflexes 4-5 times aloud: 

the period when he was in Paris. [ = the period (that) he was in Paris].

the place where they’ve gone. [ = the place (that) they’ve gone to].

the day (when) he reached there. [ = the day (that) he reached there (on).]

the day when he was born (on). [ = the day (that) he was born (on)].

the place where we stayed. [ = the place (that) we stayed at].

the time (when) you were there. [ = the time (that) you were there].

(the reason) why he did it. [ = the reason (that) he did it].

the way that she handled the situation.