Mercury rules 1st and 4th house is in 7th house in Sagittarius

Mercury in the 7th house represents communication, partnership, marriage and business contracts. Sagittarius is a sign of expansion, zeal, and optimism.

With Mercury in the 7th house, you may have a natural talent for networking, negotiating, and making connections with others. Your communication skills are highlighted, enabling you to engage with people from all walks of life and build strong relationships. You may also be drawn to careers that require excellent communication skills such as sales, marketing, or public relations.

However, with this placement, you may also struggle with decision-making in your relationships or business partnerships. Sagittarius is known for its philosophical and open-minded nature, which can make it difficult to establish a solid foundation in certain areas of your life.

It's important for you to develop your intuition and to seek balance in your relationships. You will need to learn to weigh the pros and cons of an idea or proposal and keep an open mind to different possibilities. It's also recommended that you avoid rushing into things without proper consideration and communication.

Overall, Mercury in the 7th house in Sagittarius sign is a favorable placement for those wanting to excel in communication and partnership, but also requires proper decision-making skills in their relationships and business partnerships.