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- But scientists do not know exactly how common microchimerism is. 但是科学家们并不是确切知道微嵌合体到底有多普遍。
- Scientists do not know how much and what kinds of noises are harmful to ocean animals. 对于危害海洋动物健康的噪声,其强度和种类,科学家了解甚少。
- But Chad Reissig says scientists do not know a lot of about them and how they interact with each other and caffeine. 但是查得莱斯说，科学家们对于这些物质以及它们之间和咖啡因的相互作用知道的并不多。
- Scientists do not know why dinosaurs became extinct,but some theories postulate that changers in geography,climate, ... 科学家不知道恐龙为何灭绝，但是一些理论假设地形，气候，海平面的变化将对此负责。
- But Chad Reissig says scientists do not know a lot about them and how they interact with each other and caffeine. 二，这些饮料的标签上没有提供足够的信息。三，各种饮料中咖啡因的含量差别巨大。
- Scientists do not know why there are so many more right-handed people than lefties. 科学家搞不清楚为什么惯用右手的人比左撇子多得多。
- This gene has been studied for years, but scientists did not know it was linked to itching. 此基因已被研究了好几年,但是科学家没想到它跟搔痒有关。
- Scientists do not know why dinosaurs became extinct,but some theories postulate that changers in geography,climate,and sea levels were responsible. 科学家不知道恐龙为何绝种了，但是一些理论推断是地理，气候和海平面的变化造成的。
- Scientists do not know why dinosaurs became extinct, but some theories postulate that changers in geography, climate, and sea levels were re o ible. 科学家不知道恐龙为何绝种了，但是一些理论推断是地理，气候和海平面的变化造成的。
- Scientists do not know why dinosaurs became extinct, but some theories postulate that changers in geography, climate, and sea levels were responsible.? 科学家不知道恐龙为何绝种了，但是一些理论推断是地理，气候和海平面的变化造成的。?
- Scientists do not know why dinosaurs became extinct,bue some theories postulate that changers in geography,climate,and sea levels were responsible. 科学家们不知道恐龙为什么灭绝，但是一些理论的假定，如地理条件、气候、和海水的变化是负有责任的。
- Scientists do not know why dinosaurs became extinct, but some theories postulate that changers in geography, fclimate, and sea levels were responsible. 科学家不知道恐龙为何绝种了，但是一些理论推断是地理，气候和海平面的变化造成的。
- Scientists do not know why dinosaurs become extinct, but some theories postulate that changers in geography , climate, and sea levels were responsible. 科学家们不知道为什么恐龙会灭绝，但是一些理论假设是地理、气候和海平面的变化导致的。
- Scientists do not know why dinosaurs bacame extinct, but some theories postulate than changers in geography,climate,and sea levels were responsible. 科学家们不知道恐龙为什么会灭绝;但有些理论推测是由地理;气候以及海平面的变化所导致的.
- Scientists do not know why dinosaurs became extinct, but some theories postulate that changers in geography, climate, and sea levels were responsible. 科学家不知道恐龙为何绝种了，但是一些理论推断是地理，气候和海平面的变化造成的。
- Scientists do not know exactly how the AIDS virus damages the immune system, nor do they understand why the natural antibodies developed to destroy the virus are ineffective. 科学家们尚未能确定爱滋病是如何破坏免疫系统的,他们也不明白旨在破坏这种病毒的天然抗体为什么不能发挥作用。
- Scientists do not know exactly how the virus damages the immune system, nor do they understand why the natural antibodies developed to destroy the virus are ineffective. 科学家们迄今未能确定这种病毒破坏免疫系统的机理,他们也不明白旨在破坏这种病毒的天然抗体为什么无效。
- I do not know why acids eat in metals. 我不知道酸腐蚀金属的原因。
- They do not know what the words mean. 他们不知道这些字的意思是什么。
