Complex sentence: To qualify for initial Phi Theta Kappa membership, a student must maintain a GPA of (usually) 3.5 or higher and pay a one-time international membership fee, plus any chapter or regional dues thay may apply.
Split into simpler sentences: To qualify for initial Phi Theta Kappa membership, a student must maintain a GPA of, in most cases, 3.5 or higher. They must also pay a one-time international membership fee, plus any chapter or regional dues thay may apply.