Ivo came to the science room early on Monday. He wanted to feed the class fish. The room was quiet.
周一，伊沃很早就来到了科学教室。他想给班里的鱼喂食。教室里静悄悄的。
He looked at the fish tank. He stopped at the door. The water was bright blue.
他看向鱼缸，在门口停住了脚步。缸里的水是鲜亮的蓝色。
Two orange fish swam in it. They looked fine. But the water looked very strange.
两条橙色的鱼在里面游着。它们看起来没事，可是这水看起来很奇怪。
"Ivo, you are here early," said Kamal from the door.
“伊沃，你来得真早，”卡迈勒在门口说。
"Look at the tank," Ivo said.
“看看鱼缸，”伊沃说。
Kamal walked over. His mouth opened wide.
卡迈勒走过去，嘴巴张得大大的。
"Wow! It was clear on Friday," he said. "Who did this?"
“哇！周五的时候水还是清的呢，”他说，“这是谁干的？”
"I don't know," Ivo said. "Maybe someone put paint in it."
“我不知道，”伊沃说，“也许有人往里面倒了颜料。”
"Paint is bad for fish," Kamal said. "But our fish are not sick. They swim and eat."
“颜料对鱼不好，”卡迈勒说，“可是我们的鱼没生病。它们又游又吃。”
"So it is not paint," Ivo said. "We need clues."
“那就不是颜料，”伊沃说，“我们需要线索。”
"Good idea. I look at the floor," Kamal said.
“好主意。我去看看地板，”卡迈勒说。
Ivo looked at the table. He saw a small box in the bin. He took it out.
伊沃看向桌子。他在垃圾桶里看见一个小盒子，便把它拿了出来。
"Kamal, come here," he said. "This box has a picture on it."
“卡迈勒，过来，”他说，“这个盒子上有一幅图。”
"What is it?" Kamal asked.
“是什么？”卡迈勒问。
"It is a toy castle for fish tanks," Ivo said. "The box is empty."
“是鱼缸用的玩具城堡，”伊沃说，“盒子是空的。”
"So someone put a castle in the tank," Kamal said.
“所以有人把一座城堡放进了鱼缸，”卡迈勒说。
"Yes. But I don't see a castle," Ivo said.
“对。可是我没看到城堡，”伊沃说。
They looked into the water. At the back, they saw a small tower. It was very pale blue.
他们朝水里看去。在缸的后面，他们看见一座小塔，是很淡的蓝色。
"That is the castle," Kamal said. "It is blue, but the water is much bluer."
“那就是城堡，”卡迈勒说，“它是蓝的，可是水蓝得多了。”
"Maybe the colour comes off the castle," Ivo said.
“也许颜色是从城堡上掉下来的，”伊沃说。
"Let us test it," Kamal said. "A test shows us the answer."
“我们来做个实验吧，”卡迈勒说，“实验能告诉我们答案。”
Ivo found two clear cups on the shelf. Kamal filled them with clean water from the tap.
伊沃在架子上找到两个透明的杯子。卡迈勒用水龙头里的干净水把它们装满。
"We need one more castle," Ivo said.
“我们还需要一座城堡，”伊沃说。
"The box has a spare piece in it," Kamal said. He pulled out a tiny blue flag. "It is the same blue plastic."
“盒子里有一个备用的小零件，”卡迈勒说。他抽出一面小小的蓝旗，“和城堡是同一种蓝色塑料。”
"Good. Put the flag in one cup," Ivo said. "Leave the other cup empty."
“好。把旗子放进一个杯子里，”伊沃说，“另一个杯子什么都不放。”
Kamal put the flag in the first cup. They both watched the water.
卡迈勒把旗子放进第一个杯子。两个人一起盯着水看。
"Nothing happens," Kamal said.
“什么都没发生，”卡迈勒说。
"We must wait," Ivo said. "The tank was warm. Maybe this water needs to be warm too."
“我们得等等，”伊沃说，“鱼缸里的水是温的。也许这杯水也得是温的。”
Kamal ran to the sink. He filled a cup with warm water. He put the flag in it. Ivo looked at the clock.
卡迈勒跑到水槽边，接了一杯温水，把旗子放进去。伊沃看了看钟。
Five minutes passed. Ten minutes passed.
五分钟过去了。十分钟过去了。
"Look!" Ivo said. "There is a blue cloud around the flag."
“看！”伊沃说，“旗子周围有一团蓝云。”
The water in the warm cup turned pale blue. The water in the cold cup stayed clear.
温水杯里的水变成了淡蓝色，冷水杯里的水依然清澈。
"The warm water pulls the colour out," Kamal said. "That is the answer."
“温水能把颜色拉出来，”卡迈勒说，“这就是答案。”
"But who put the castle in the tank?" Ivo asked.
“可是是谁把城堡放进鱼缸的呢？”伊沃问。
"We have a second clue," Kamal said. "Look at the floor."
“我们还有第二条线索，”卡迈勒说，“看看地板。”
On the floor, there were small blue drops. They went from the sink to the tank. A blue hand mark was on the chair too.
地板上有一些蓝色的小水滴，从水槽一直延伸到鱼缸边。椅子上还有一个蓝色的手印。
"Someone with blue fingers stood on this chair," Ivo said.
“有个手指是蓝色的人站在过这把椅子上，”伊沃说。
"Who has blue fingers on Monday?" Kamal asked.
“周一谁的手指会是蓝的呢？”卡迈勒问。
Just then, the door opened. Joss came in with his bag. He looked at the tank, and his eyes got big.
就在这时，门开了。乔斯背着书包走进来。他看了看鱼缸，眼睛一下子瞪大了。
"Oh no," he said. "It worked too well."
“哦不，”他说，“效果太好了。”
"What did you do?" Ivo asked.
“你做了什么？”伊沃问。
"I bought the castle on Sunday," Joss said. "The fish had no house. I put it in the tank in the evening."
“我星期天买了那座城堡，”乔斯说，“鱼没有房子住。我晚上把它放进了鱼缸。”
"Look at your hands," Kamal said.
“看看你的手，”卡迈勒说。
Joss held up his hands. His fingers were bright blue.
乔斯举起双手。他的手指是鲜亮的蓝色。
"I washed them two times," he said. "The colour does not go away."
“我洗了两遍，”他说，“颜色洗不掉。”
"The castle did that to the water, too," Ivo said. "The tank is warm. The blue plastic gives its colour to the water."
“城堡把水也弄成这样了，”伊沃说，“鱼缸里的水是温的，蓝色塑料把颜色放进了水里。”
"Is it bad for the fish?" Joss asked.
“这对鱼不好吗？”乔斯问。
"They look fine," Ivo said. "But we must take the castle out. We must change the water."
“它们看起来没事，”伊沃说，“不过我们得把城堡拿出来，还得换水。”
"Let me help you," Joss said. "I am sorry."
“让我来帮你们吧，”乔斯说，“对不起。”
"It was a nice idea," Kamal said. "But the castle is not a good one."
“这主意挺不错的，”卡迈勒说，“只是这座城堡不太好。”
Ivo took the net from the shelf. Joss took a clean bucket from under the sink. Kamal opened the tank lid.
伊沃从架子上拿来渔网。乔斯从水槽下面拿来一只干净的桶。卡迈勒打开了鱼缸盖。
One orange fish swam up. It looked at them.
一条橙色的鱼游了上来，看着他们。
"Do not worry," Ivo told the fish. "You get a clear home again."
“别担心，”伊沃对鱼说，“你们很快又有一个清澈的家了。”
