Answer:
120 words
Explanation:
There are only three possible letters, assuming words can be 1, 2, 3 or 4 letters long:
The number of 1 letter words is 3
The number of 2 letter words is 3² = 9
The number of 3 letter words is 3³ = 27
The number of 4 letter words is 3⁴ = 81
The total number of possible words is:
This tribe's language has 120 words.