There was a famous American painter named Winslow Homer. Since Art History class in college, I had always admired his works and I was lucky to see a large exhibition of his works when I was in my early 30’s. It was at this event that I bought a print of his painting, Snap the Whip. Until I retired from teaching it always hung in my classroom.

I thought it truly captured(捕捉)the freedom and fun of childhood. In the painting,a group of young boys are playing a game arm in arm on grass ground in front of a farm house. They are jumping and laughing wildly with great joy. One of the boys is falling down to the ground. They are not even wearing shoes!

During my last year of teaching, there was a young woman in her first year of teaching right next door to me and we got to be good friends. She had been an art student before switching to education. Her eyes were drawn immediately to this print when she entered my room. So on my last day of teaching, after the students had left, I took the painting off the wall and walked next door and gave it to her.

She was really surprised, but very pleased to have it. I was pleased that she liked it and all the students she would have would treasure it as much as I had. We found the perfect place for it on one of her walls and hung it together. Thank you for bringing back this wonderful memory for me.

As you read, remember: gifts from the heart are the best ones you’ll ever receive.

According to legend (传说), a young man while moving about the desert came across a spring of delicious clear water. The water was so sweet that he filled his leather canteen so he could bring some back to an elder who had been his teacher. After a four-day journey he gave the water to the old man who took a deep drink, smiled warmly and thanked his student for the sweet water. The young man returned to his village with a happy heart.

Later, the teacher let another student taste the water. He spat it out, saying it was very smelly. It had become no longer fresh because of the old leather container. The student asked his teacher, “Master, the water was smelly. Why did you pretend to like it?”

The teacher replied, “You only tasted the water. I tasted the gift. The water was simply the container for an act of loving-kindness and nothing could be sweeter.”

I think we understand this lesson best when we receive gifts of love from young children. Whether it’s a piece of paper or a ruler, the natural and proper response (反应) is appreciation and we express thankfulness because we love the idea within the gift.

Gratitude (感激) doesn’t always come naturally. Unfortunately, most children and many adults value only the thing given rather than the feeling in it. We should tell ourselves and teach our children about the beauty and purity of feelings and expressions of gratitude. After all, gifts from the heart are really gifts of the heart.

Many biologists are drawn to ocean animals like sea turtles and whales. For me, the pale, blind creatures in the world’s darkest caves are more attractive. As an underwater cave ecologist, I find and name new species. I have described eight new species of sponges (海绵物种) so far, seven of which live only in caves. Sometimes I count the population of organisms to see how their numbers change over time. I also study how different species interact with one another and their environment.

When I start diving with my team members, there’s natural light around us, but as we div e farther, it turns dark, and we switch on our lights and follow the cave line — a thin thread explorers leave behind for divers to find their way in and out of the cave. While some caves are just a few meters long, some stretch over 300 kilometers and could be deeper than 50 meters. Diving at this depth, you might fall in narcosis,a state where the brain feels like it’s on a high, similar to being drunk. We might run into trouble an hour or so away from the cave entrance.

But the mysterious (神秘的) world we see inside is worth the risk. I remember diving into El Aerolito Cave on Cozumel Island in Mexico, where I recorded 101 species. My most exciting encounter to date has been with remipedes — poisonous wormlike creatures found only in underwater caves. It took me around 200 dives before I came face to face with about 15 of them hidden deep in the caves of Cozumel.

These delicate ecosystems are rapidly changing due to water pollution, climate change, and construction activities. We might lose the many life forms in these deep, dark worlds before we can even begin to understand them. I’m determined to explore all I can while they still exist. I’m taking advanced diving lessons and learning new laboratory techniques so that I can go even deeper into understanding this environment.