2. (8 points) Shuaishuai finished memorizing English words in five days. It is known that in the first three days, he memorized $\frac{1}{2}$ of all the words, and in the last three days, he memorized $\frac{2}{3}$ of all the words, and he memorized 120 fewer words in the first three days than in the last three days. Therefore, Shuaishuai memorized $\qquad$ English words on the third day.
【Solution】Solve: $120 \div\left(\frac{2}{3}-\frac{1}{2}\right) \times\left(\frac{2}{3}+\frac{1}{2}-1\right)$
$$
\begin{array}{l}
=120 \div \frac{1}{6} \times \frac{1}{6} \\
=120 \text { (words) }
\end{array}
$$

Answer: Shuai Shuai memorized 120 English words on the third day.
Therefore, the answer is: 120.