S1 문장의 [______]에 들어갈 단어는?

난이도 고난도 · 힌트를 덜 열수록 높은 점수 (현재 5점)
One reason conversational life can lack depth and [______] is that we easily fall into using formulaic questions to open a dialogue ― How are you?, What was the weather like?, What do you do?, How was your weekend?