The phrase "conceive of" means to imagine or form a mental image of something. There are several synonyms for this phrase, such as "envision," "picture," "visualize," "perceive," "grasp," "comprehend," "understand," "conceive," "apprehend," and "realize." All of these words convey the idea of forming a mental picture or understanding of something, but each one has slight differences in meaning. For example, "envision" implies that the mental picture is clear and detailed, while "picture" suggests a more static and less nuanced image. Choosing the right synonym can convey a specific nuance or tone to your writing, making it important to choose carefully.