第 40 題至第 43 題為篇章結構，各題請依文意從四個選項中選出最合適者，答案選用不能重複 Research shows that smiling has many positive effects on our health. This might explain why the people in the studies with bigger smiles had longer lives. __40__ It also lowers blood pressure. Smiling can affect the brain in the same way as exercise. For example, it increases the amount of feel-good hormones such as serotonin and endorphins. __41__ Furthermore, recent brain research shows that just the act of smiling can actually make us happier. __42__ But then, our smiles send a message back to the brain that makes us feel even happier. Smiling is clearly good for us. __43__ It is easy to see that smiling is much more than just an expression of happiness. It’s a powerful tool for maintaining both emotional and physical health.