直线有几个线段

以德报怨,何以报德? I notice him go into the teachers （被动语态） I noticed him ( )the teachers' office just now.A.went into B.go into C.was going into D.came out of 请问要选哪一个 在所有彗星中,哈雷彗星是最著名的,但是哈雷本人并没有看到过它是吗? 成语( )首怒放 我的英语口语不是很好,就怕面试自我介绍做不好怎么办?面试自我介绍在语言上有什么要注意的? 过几天就面试了,英语口语不是很好,很紧张.怎么办 網友英語填空求解（在綫等）The detectives went into the building and waited _____.A,in B,into C,...網友英語填空求解（在綫等）The detectives went into the building and waited _____.A,in B,into C,inside D,for.那一個是正確 We saw him ________the building and went upstars A go into B went into 为什么选A,不是说AND 的话,时态上要一致吗 请以“?”为题写一篇作文,文体不限,举例有？我的成长伙伴 让我有了一个新发现 的启示 the detectives went into the building and wait for +名词 为什么有些句子能直接以动词短语结束为什么这个句子还要加名词? 帮忙写一篇作文 ______令我心醉 .文体不限 .怎么个写 、 1,已知函数f(x)=(x^2+3)/(x-a).解不等式f(x)a时,f(x)的最小值为6,求a的值2,已知直线l1过点(0,t)方向向量为(1,1)直线l2过点(t,1)方向向量为(1,-2)且l1与l2的交点为p,当t变化时,动点p的轨迹方程为. 求轨迹方程在平面直角坐标系中,O为坐标原点,已知A（3,1）,B（-1,3）两点,若C满足OC=aOA+bOB,其中a,b∈R,且a+b=1,求点C的轨迹方程.麻烦给个过程哦,顺便解释一下什么是轨迹方程（百科里的没看懂… 向量与轨迹方程有难度设AB是圆0 X^2+Y^2=9的动弦 ,|AB|=3 定点C(C,0)和动点P满足（向量）PA+PB+3PC=0求点P轨迹 设A是空间内任一点,n向量是空间内任一非零向量,则适合条件（AM向量）×（n向量）=0的点M的轨迹是? 向量和轨迹方程的结合题..有点小难度....设x,y∈R,向量i、向量j为直角坐标平面内x、y轴正方向上的单位向量,若向量a=x*向量i+(y+2)*向量j,向量b=x*向量i+(y-2)*向量j,向量a的模+向量b的模=8.(1)求点M( He is busy.He keeps ____ these days. A work B to work C works D working 要理由. His wealth,is based on his company,Microsoft,of which he owns 39% of the shares.请帮忙分析这句话,特别是 of which he owns 39% of the shares这个定语从句,这种介词+which/whom/whose的,我一看就慌 a day's work a-day-work区别 急求!能不能再具体说一说加横线与没加横线的区别越详细越好~本人偏笨最好在通俗易懂一点 On Monday Mr.O'Donnell sent a memo around the office of his London stockbroking company.翻译 The boss kept him working all day.其中working可以换成to work吗 同义句转换 Mr King closed all the windows and left the office改成 Mr King left the office _______ all the windows _______. Didney opened his first movie company in the back of an office.中的back of an 如题,给出的翻译是：迪斯尼在一所办公室里开办了他的第一家电影公司.back of an office作何解呀?什么习惯的用法吗? 我能随时问你关于物理的题目吗? 为什么说弹簧伸长越长，拉力越大这句话错的 in working days ,还是on working days After the patients went into the office,＿＿working.A.only a doctor did they see B.only a doctor saw they C.only a doctor they saw D.only a doctor had they seen After we went into Mr.Lee office he asked us [ ]A,to seat B ,seat C,to be seated D,seating【写原因】 After we went into Mr.Lee 's office he asked us [ ] .【 说原因】A,to seat B,seat C,to be seated D,seating After a quick breakfast, I went into the lecture hall in a hurry. 全文是要它的全文 不是这句话的翻译 So much love, a litte time ! 是什么意思