lobes of mammary gland

例句：

1. 1. The mammary gland is responsible for producing milk and other bodily fluids.
   乳腺腺负责产生奶和其他体液。
2. 2. The lobes of the mammary gland are where the milk-producing cells are located.
   乳腺腺的叶是产奶细胞所在的地方。
3. 3. During pregnancy, the mammary glands enlarge to produce more milk for the developing fetus.
   怀孕时，乳腺腺会增大以产生更多的奶供胎儿发育。