“头戴冠者,文也;足付距者,A____也;敌在前敢斗争,B____也;见食相呼,C____也;守夜不失时D____也。”
设集合A={x|x2﹣(a+3)x+3a=0},B={x|x2﹣5x+4=0},集合A∪B中所有元素之和为8,则实数a的取值集合为( )
有科学家研究发现,氧气可通过高能真空紫外线照射二氧化碳直接产生,该化学反应模型如图所示,关于该反应的说法错误的是( )
给带点字选择正确的读音。
①我爸爸是一位教(jiāo jiào) ____师,他总是手把手教(jiāo jiào) ____ 我写字。
②王小宁是个好(hǎo hào)____ 学上进的好(hǎo hào)____ 孩子。
下图表示哺乳动物胚胎工程的有关操作流程。下列叙述正确的是( )
根据短文内容判断下列句子正误。
Dear Mum,
How are you? I had fun with my cousins last week.On Monday we went to a restaurant.We ate some delicious food.On Tuesday we went to a zoo.We saw many animals.On Wednesday we played ping-pong.On Thursday we stayed at home and watched TV.On Friday we went shopping.I bought a pair of shoes.Tomorrow I'll be back home.
Yours Ann