四面体对棱相等

已知：如图,△ABC是边长3cm的等边三角形,动点P、Q同时从A、B两点出发,分别沿AB、BC方向匀速移动,它们的速度都是1cm/s,当点P到达点B时,P、Q两点停止运动,设点P的运动时间为t（s）,（1）当t为何 已知:如图,△ABC是边长3cm的等边三角形,动点P,Q同时从A,B两点出发,分别沿AB,BC方向匀速移动,它们的速度都已知：如图,△ABC是边长3cm的等边三角形,动点P、Q同时从A、B两点出发,分别沿AB、BC方向 已知：如图,△ABC是边长为3cm的等边三角形,动点P、Q同时从A、B两点出发,分别沿AB、BC方向匀速移动,它们的速度都是1cm/s,当点P到达点B时,P、Q两点停止运动,设点P的运动时间t（s）,（1）求△ABC 改错：Did the teachers took pictures in the park?错在哪里?请改正. Did you take pictures in the park?（改为陈述句）I took...还是You took... 笨鸟先飞早入林后半句.是不是笨人勤学早成材? though he was badly hurt,the driver managed to get out of the car and "got" help.he preferd to stay at home watching TV rather than go to the concert.都是连词,为什么前一个后面过去式后一个是go? This hurt A.a few B.a little I have lots of milk．对lots of 提问快 She didn't want the teddy bear的同义句 How Dose It Feel中文翻译 how dose it feel歌词 good 有副词形式吗?good 可以加ly变成副词吗?还是只能用well good的副词是什么 good副词 good的副词 If I ____ you tomorrow, I will give you the receipt.A. see B. will see请问大家哪个是主句,哪个是从句?这个句子是虚拟语气还是条件句? All 435 seats in the U.S.House of Representatives are up for grabs,as are 33 seats in the 100-member Senate. the Democratic Speaker of the House of Representatives She said that the show starts at 10:30 tomorrow morning.这句话怎么会前面用said后面用starts? good的副词是什么啊? 补全对话 Look ,Lucy There will () a fashion show tomorrow .Would you ()补全对话A.Look ,Lucy There will () a fashion show tomorrow .Would you () to come with me B.Yes.I’d love（）.Look how beautiful the clothes（）!A.I agree () you .Look She will name him whatever she wants to.为什么后面要加to.do whatever you want为什么后面不加to?不是问句..就是DO开头Do whatever you want!为什么不是Do whatever you want to!不好意思 还不是很明白 tomorrow I'll ring you 这句话的主语是什么? i'll gI've you a ring tomorrow是什么意思 tomorrow I'll ring you 中I后面的的 in this experiment,they were woken up 一个选择题,关于现在完成进行.in this experiment,they were woken up several times during the night,and asked to report what they ______.A,had just been dreaming. B.are just dreaming C.have just been 请把下列句子适当的改写为祈使句：(1)stand up (2)stand in line (3)say"good morning"(4)point to the blackboard(5)show me your books(6)sing a song(7)be quiet(8)sit down 什么叫祈使句?(造一个句子) The,has,encouragement,and,a,great,been,please,play,of,the,success正理成一句话 阅读下面文字,完成（1）―（3）题.花草树木,同样具有人的性格、人的风cai、人的品德.我喜欢倾听竹的低唱,因为他有洒脱的风度刚直的气节；我喜欢欣赏菊的风雅,因为他有清秀的姿态ling霜 What mustn't we do in the forest on at home中文翻译