When describing a place or situation, "are thick with" can be replaced with synonyms that suggest a dense, crowded or concentrated environment. For example, "are crowded with" can be used to describe a busy train station or shopping mall. "Are teeming with" can be used to describe a bustling city street or a lively marketplace. "Are swarming with" can be used to describe an insect-infested area or a heavily populated nightclub. "Are saturated with" can be used to suggest abundance or excess, such as a room filled with fragrant flowers or a news outlet full of sensational stories. These synonyms allow for more dynamic and descriptive language in writing or conversation.