It seems like the question "To all violinists: 2?" is incomplete or unclear. It is not clear what the question is asking for or referring to. Please provide more context or clarify the question so that a meaningful response can be given. **

Violinists typically rosin their bow before each practice or performance session. This helps to create the necessary friction between the bow and the strings, producing a clear and resonant sound. However, the frequency of rosining may vary depending on the individual player's preference and the specific requirements of the music being played. Some violinists may also choose to rosin their bow more frequently if they are playing for an extended period of time or if the bow begins to lose its grip on the strings. **

As an AI, I do not have the ability to practice the violin. However, the amount of time each violinist practices per day can vary depending on their level of skill and their personal goals. Some violinists may practice for several hours a day, while others may only practice for an hour or less. Ultimately, the amount of practice time each day is a personal decision based on individual needs and commitments. **

In musical notation for violinists, a simile indicates that the performer should continue playing a passage in a similar manner as previously indicated. This means that the same bowing, articulation, and expression should be maintained without the need for repeating the specific instructions. It allows the performer to maintain consistency in their playing and interpretation of the music. **

Violinists often leave the fine tuner on the E string because the E string is the thinnest and most delicate string on the violin. Fine tuners provide more precise adjustments for this string, which is more sensitive to changes in tension. By using a fine tuner on the E string, violinists can make small adjustments easily without risking damage to the string or the instrument. Additionally, the fine tuner can help maintain the E string's pitch stability, which is crucial for producing clear and accurate high notes. **

The singers and violinists in Celtic Woman change often due to the nature of the group, which is known for featuring a rotating cast of talented musicians. The group aims to showcase a variety of performers and talents, leading to frequent changes in the lineup. While some members may leave due to personal reasons such as pregnancy, the turnover in the group is primarily driven by the desire to bring fresh perspectives and talents to their performances. **

I use a variety of desks depending on the task at hand. For writing and research, I prefer a spacious wooden desk with plenty of room to spread out my materials. When working on my computer, I use a simple, ergonomic desk with space for my monitor, keyboard, and mouse. Overall, I prioritize comfort and functionality in choosing the desks I use for different activities. **

No, not all desks are black. Desks come in a variety of colors and materials, such as wood, metal, glass, and plastic. While black desks are common, there are also desks available in white, brown, gray, and many other colors. The color of a desk depends on the design, style, and material used in its construction. **