外语学习 英语考试
1. They came to China in 1990.(变一般疑问句)
Did they come to China in 1990?
2. I was ill for two days last week? (同上)
were you ill for two days last week?
3. The twins go to school on foot every day. (同上)
DO the twins go to school on foot every day?
4. She washed the clothes last Sunday. ( 变否定句)
She didn't wash the clothes last Sunday.
5. She is going to shopping tomorrow. (变否定句)
She isn't going to shopping tomorrow.
6. My mother likes her students. (变一般疑问句)
Does My mother like her students?_________________________________
7. Do you watch TV on Sunday? (用last Sunday 改写成过去时态的句子)
Did you watch TV on Sunday?
8. Wei Hua bought a new pen yesterday. (变否定句)
She diidn't buy a new pen yesterday.
9. We had a meeting the day before yesterday. (变一般疑问句)
Did you have a meeting the day before yesterday?
10. They had a good time last Sunday.
Did the twins have a good time?
氨基酸是怎样合成的
必需氨基酸一般由碳水化合物代谢的中间物，经多步反应（6步以上）而进行生物合成的，非必需氨基酸的合成所需的酶约14种，而必需氨基酸的合成则需要更多的，约有60种酶参与。生物合成的氨基酸除作为蛋白质的合成原料外，还用于生物碱、木质素等的合成。另一方面，氨基酸在生物体内由于氨基转移或氧化等生成酮酸而被分解，或由于脱羧转变成胺后被分解。扩展资料氨基酸在人体内通过代谢可以发挥下列一些作用：①合成组织蛋白质；②变成酸、激素、抗体、肌酸等含氨物质；③转变为碳水化合物和脂肪；④氧化成二氧化碳和水及尿素，产生能量。参考资料来源：百度百科-氨基酸
求初高中所有化学名词的英文表
properties 特性,属性
accuracy 准确
precision 精确性
physical changes 物理变化
chemical changes 化学变化
mixture 混合物
heterogeneous mixtures 不同种的混合物
homogeneous mixtures 同种混合物
pure substance 纯正物
element 元素
compound 混合物
atomic number 原子序数
mass number 原子质量
atomic symbol 原子符号
isotopes 同位素
radioisotopes 放射性同位素
periodic law 周期律
periodic trends 周期性
valence electrons 电子化合价
Lewis structure 结构
stable octet(octet) 稳定结构
ion 离子
anion 阴离子
cation 阳离子
ionization energy 游离能
electron affinity 亲和力
我对化学一窍不通
这些是我一个学化学的同学说的
希望能帮到你
