The combination of present tense and present perfect tense: used to describe current situations and experiences from the past until now. For example, "I do recognize some of my neighbors" uses present tense, while "we haven't really gotten into deep conversations" uses present perfect tense.
The use of parallel structure: to describe the way of interacting with neighbors. For example, "we exchange greetings or have occasional chats in the elevator or hallway." This sentence uses parallel structure to list different ways of interacting with neighbors.