The phrase "were visible" refers to something that can be seen or observed. There are several synonyms that can be used in place of this phrase. For example, the phrase "were apparent" can be used to describe something that is easily visible or noticeable. The phrase "were clear" can be used to describe something that is easily seen and understood. Additionally, the phrase "were evident" can be used to describe something that is clearly visible and cannot be denied or ignored. Other synonyms for "were visible" include "were obvious", "were perceptible" and "were discernible". Ultimately, the use of synonyms allows writers to add variety and depth to their language, making their writing more engaging and effective.