类型 构成方法 例词 one, two, three, four, five, six, seven, eight, nine, ten, eleven, twelve thirteen, fourteen, fifteen, sixteen, seventeen, eighteen, nineteen twenty, thirty, forty, fifty, sixty, seventy, eighty, ninety 1-12 单独的词 13-19 在3-9的词尾加上“-teen” 20,30,40-90 以“-ty”结尾 100,1000,1000,000, 1000 000 000, 百，千，百万，十亿都有具体量词 one/a hundred, one/a thousand, one/a million, one/a billion 21-99 “几十”和“个位”之间用连字符“-” twenty-three,forty-eight 101-999 “百位”后“十位”前加“and” 826: eight hundred and twenty-six 先从右向左每三位数加一逗号，从右向左第一个逗号为thousand,第二个为million,第三个为billion,然后每三位为一单位从左向右读。 1,000以上 1，234，567，892: one billion, two hundred thirty-four million, five hundred sixty-seven thousand eight hund red and ninety-two
3.序数词的构成：
类 型 one, two, three four～nineteen 构成特点 单独记忆 在基数词尾加-th 例词及缩写式 first (1st), second (2nd), third (3rd) fifth (5th), ninth (9th), twelfth (12th) twentieth (20th), fiftieth (50th), fortieth (40th) twenty-first (21st), ninety-ninth (99th) -ty结尾的词 把y→ie，在基数词尾加-th 以1～9结尾的多位数 变个位数为序数词即可 第 11 页，共 35页
hundred, thousand, 在基数词尾加-th即可 million, billion hundredth (100th) thousandth (1,000th) millionth (1,000,000th) billionth (1,000,000,000th)
4.序数词的用法：
序号 1 2
用法特点 前面要加the 前面用a/an表“又一，再一” 举 例 He’s always the first to get to meeting-room. He’d better try a fourth time. 公共英语等级考试PETS二级语法资料汇总(五)介词
(五)介词
1.介词的概念及分类：介词是一种虚词，不能单独在句中充当成分，要与宾语一起构成介词短语才可在句中充当成分。介词按形式分为简单介词、复合介词、短语介词、特殊介词和双重介词。
分类 例 词 at, about, above, after, as, but, by, down, during, except, for, from, in, like, near, off, of, on, opposite, over, past, round, since, through, till, to, under, until, up, besides, between, beyond, with, across, against, along, among, around, before, behind, below, beside inside, outside, onto, into, toward(s), upon, within, without along with, together with, according to, ahead of, as for, as to, because of, due to, except for, owing to, out of, up to, by means of, by the side of, by way of, in front of, in spite of, as far as concluding, regarding, considering, save until after, until before, Saturday, except, on duty 简单介词 按 形 式 分 特殊介词 双重介词 复合介词 短语介词 第 12 页，共 35页
按 功 能 分 空间（地方、位置、方向、范围、界限、包括、排除） about, above, across, after, against, along, among, (a)round, at, before, behind, with, below, beneath, beside, besides, between, upon, save, beyond, but, by, concerning, down, on, out of, outside, over, past, through, throughout, towards, under, up after, before, as, between, by, during, for, from, in, on, over, past, till, until, up to, within, through, throughout 时间 原因理由根源（目的，内容等） about, according to, as, because of，due to，owing to，on acount of, from, of, on, with, regarding, concerning, considering, through, by, under, for
2．容易混淆的介词：
区别 讲解 例句 I get up at six o’clock. at表示“在几点几分”（单位最小）；on表示“在具体的某一天或某天上午（下午晚上等）”； It happened on a spring morning. There are seven days in a week. at, on, in 表 时 间 的 介 词 in表示“在几天、周、月、年”。 in the morning / evening / afternoon；at noon / night / dawn / sunrise / sunset / lunch / dinner / supper, etc. She has lived here for six years. He was in English during the war. In those days he was poor. They waited till/until 10:00. They didn’t leave until/till 10:00. for后加一个“表时间段的具体during, for, 单位（常用复数）”；during强调in “持续”或“某活动”期间；in指在一段时间内。 till, until till/until构成的短语修饰“持续性动词”，“非持续性动词”要用“否定式”。 “after+时刻或时段”，“?以后”，终点时间在过去或将来；而“since+时间点”，“自从?以来”，终点在说话的时刻。 She’ll be back after eight o’clock. She’s lived here since 2002. after, since 第 13 页，共 35页
He’ll leave after 11:00. “in+时段”，“?以后”，用于将He left after 11:00. 来时；“after+时刻或时段”，“?以后”可用于将来时或过去时。 She left after a few hours. She’ll be back in half an hour. at指一个“点”或“小地方”； They arrived at the village at ten. at, on, in in指一个“地区”或“大地方”Your pencil is in the desk. 空间内；on在某一平面或线上Your pencil is on the desk. 面。 There’s a book on the desk and a pen beneath the book. on“与物体接触”反义词为on, above, “beneath”；over“在?正上方”There’s a lamp over the desk and a bag over 反义为“under”；above“在?under the table. 的上方”反义词为“below”。 Jack’s bedroom is above mine on the second floor. across“表面跨过”； over, across, through“从中间或从头至尾穿through 过”； over“从上空越过”。 at靠得“最近”； beside“在并排一条线上”； at, beside, by“在并排一条线上”； by, next to, near next to“在顺序上紧靠旁边”； near 靠得“最远”，不表明确方向或顺序。 about表示周围是随意的，不规则的；round或around(二者无多第 14 页，共 35页
in, after 表 空 间 位 置 及 方 向 方 位 的 介 词 He’s swimming across the river. They walked through the forest. A plane is flying over the city. Let’s meet at the school gate. The building beside the library is the shopping center. The boy standing by my side is from Shanghai. Who’s sitting next to/beside Mr.Steve? about, round, Don’t leave the toys about the
around. 大差别)的周围则是较完整的一个圈。 meeting-room. They are sitting round/around the table. to “运动的方向，目的地”； to, for, at for “动身出发的目的地”； at “有意攻击的目标”。 up指“往上，往北，大地方，靠拢”； up, down down指“向下，往南，向小地方，往开走”但在一市区，去中心区用down,去郊区等用up。 in表“在某地区内”； on, in, to on表“接壤”； to表“在某地区以外”。 between指“两者之间”； Throw it to me. He’ll leave for Shanghai. He threw the ball at that boy. They are going up the hill. They are going down river. I’m going down town shopping. Shanghai is in the south of China. Hunan lies on the north of Guangdong. Xichang lies to the south west of Chengdu. There’s a river between the two villages. between,among among指“在三者以上之间”。 There’s a small house among the trees. besides“除?之外还有，”实际不排除； except“除?外”表“排除”，不放在句首； except for表整体肯定补充细节，表除去整体中的一部分； except that“除了?外”，后接从句； I love music besides sports. The house is never used except in winter. The bus is empty except for an old woman. I don’t know Peter except that he’s an Japanese. There’s nothing but a chair in the room. besides except except for except that but but for But for your help,I wouldn’t have finished but通常与all, no, every, where, my homework. who what及有些它们的合成词连用；but for“要不是”，后面第 15 页，共 35页