“Good morning, Teddy,” I said to my little brother. “Are you ready to get to work?”

“First let’s find a missing dragon!” said Teddy. My brother has a ________ imagination. “I don’t think anybody we know is missing a dragon,” I said. “We are not heroes. We’re ________. We find things like missing shoes and hats.”

“My friend Peter is missing his dinosaur.” Teddy said.

“Stop ________ around,” I said. “Dinosaurs have disappeared.”

“It’s his toy,” Teddy said.

That sounded ________. I asked Teddy to tell me everything he knew.

Most days after school, my brother goes across the street to Peter’s house to play Go Fish. But yesterday, Peter ________ to play any games. His eyes were red. He kept talking about his Bruno. We walked to Peter’s house to check things out.

Peter was in his yard. I wrote before going through my ________ questions.

“When did you last see Bruno?” I asked.

“Yesterday, in the morning,” Peter answered.

“Where did you see him?”

“He was with me. I was holding him,” Peter said.

“I have a question,” said Teddy. “What did you eat for breakfast yesterday?”

“Oatmeal (燕麦粥),” Peter said.

“With milk?” asked Teddy.

Does that really ________? I thought.

“You never know what’s a ________,” he told me. I smiled. I was the one who had taught him that!

We went inside Peter’s house. “Let’s pretend (假装) it’s time for ________,” I told Peter. “You come downstairs. Then what?” Peter sat on a chair and held his imaginary dinosaur with his left hand. He pretended to eat and eat and eat. Then he went into the kitchen and used both hands to pull out a chair. He set the chair down in front of the fridge and put away the imaginary milk with his right hand.

I looked at my notes again. “Wait,” I said. “How did you hold Bruno while you were carrying the chair?” I looked over at Teddy, who nodded knowingly.

Teddy ran into the ________. When he came out, he was holding a toy dinosaur.

Teddy was turning out to be a good detective!

You may know that things like car emissions (排放) and plastics are bad for our Earth. But how about washing your jeans? Scientists find that washing a pair of jeans can give out about 56,000 microfibers (微纤维). These fibers are less than 5 millimeters (毫米) long. They can go from our washing machines all the way to the sea. This is bad for the Earth and even harms our health.

“Look! Letters from Leo! Granny will be excited!” Mom said.

Andy turned toward his mother. “Leo?”

“Granny’s oldest and favorite brother. He made her that special box that sits beside the window—locked up. The key’s been lost forever. Now about those letters...Granny will want them.”

Andy picked that special box and letters up, then took them to the kitchen. “What did you put in the box, Granny?” Andy asked.

“Nothing! I knew Leo would be joining the army soon. Just before he left, he locked my box and hid the key. He said he’d invented a word game for me and promised he’d send clues. We got letters but not one clue. Leo’s final letter arrived after we heard the heartbreaking news. Mother was so sad. She tore (撕) it in half.”

Granny watched Andy spread the letters on the table. She whispered, “I always thought mother threw away all of Leo’s letters.”

Andy pointed at one letter in two pieces. “This must be the last letter Leo sent home.”

Granny picked up one half of the letter, and read, “Dearest Littlest Sister...”

“Leo did send clues. Let’s tape the halves together.” Andy said.

Andy read, “Ewe reed four make?”

“Nonsense words,” Granny said.

Andy looked at the paper, then said, “Wait! If we read down, instead of across—in columns (列), not rows.” He read the words one by one “You need to read this aloud for it to make some sense.”

Granny’s eyes opened wide. “Leo was using homophones (同音异形词)!”

She began to read, “Go to the room where we ate. See the flower like the sun?”

Granny smiled. “The dining room is where we ate. The painting of a sunflower...”

Andy was on his way. In a few seconds, he returned, carrying the painting. They discovered another clue printed in light pencil on the back. Andy read, “Look above the hole where rain does not come down. See the broken time piece? There! Inside!”

He ran to the fireplace then gave the clock to Granny. “This clock has never kept time.” Granny opened the clock’s tiny glass door and reached inside. “All those years. It’s been right here.” She opened the box with the key and looked into it.

There is a photo of a girl and her big brother. On the back of the photo was printed: I NEW you’d worked it out. Use this box for all your special treasures. Love, Leo.

Granny gently placed the photo and the letters inside the box. “My treasures,” she said.

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On Feb. 15, a new video model called Sora promises to create a video up to a minute long from a short text description. Just tell Sora your idea, and watch it make a video right before your eyes. Sora is described as “eye-popping”, “world-changing”, and “breathtaking, yet scaring.”

The videos from OpenAI’s Sora are full of details. One video of a Tokyo street scene shows that Sora has learned how objects fit together in 3-D: the camera goes into the scene to follow a couple as they walk past a row of shops. Sora knows how things should look in real life.

Sora looks at many videos and learns from them by breaking them into very small bits. It uses these bits to make a new video. The new video is grey at first and very messy. Then, Sora fixes the video until it looks good and smooth. Sora also gets help from ChatGPT, which turns the user’s short sentences into clear instructions. This helps Sora make the video just as you asked.

Sora may find “busy” pictures hard to understand. For example, when a person moves, things around them change. In one video created by Sora, a grandma blows the candle on a birthday cake, but the flame (火焰) doesn’t move. Sora may not be able to tell “left” from “right”.

OpenAI also says that Sora deals with occlusion well. But one problem is that they fail to follow objects when they are out of sight. For example, if a truck passes in front of a street sign, the sign might not reappear afterward.

In a video of a papercraft underwater scene, Sora has added what looks like cuts between different pieces of footage (镜头), and the model has kept the same style between them. But it’s not perfect. In the Tokyo video, cars to the left look smaller than the people walking beside them. They also pop (突然出现) in and out between the trees. “There’s some work to be done,” says Brooks. “For example, if someone goes out of view for a long time, they won’t come back.”

“Sora seems like a very important leap forward,” says Sam Gregory, a human rights organization that specializes in the use and misuse of video technology. “But there are two sides of the coin,” he says. “The meaningful abilities help many more people to be storytellers using video. And there are also possibilities for misuse.”

OpenAI has also realized the risks that come with a video model. The OpenAI team plans to draw on the safety testing. “We’ll need to get more feedback (反馈) and learn more about the types of risks that need to be solved with video before it would make sense for us to put Sora into use,” says Ramesh.