This paper discusses how tense, aspect and mode (TAM) are marked in Sani Yi, a Tibeto-Burman language spoken in Yunnan, China. There are two main strategies used by Sani to express TAM distinctions: 1) particles, and 2) verbal auxiliaries. These strategies are not always easy to tease apart. If the line were clear-cut, a verbal auxiliary would exhibit verb-like behavior whereas a particle would not.