重新定位和介词短语

介词 are common; 他们 are not flashy. They are sometimes very little words, 就像 on, in, 不像; sometimes 他们 are two words, 就像 根据. A preposition combined 与 a noun (or pronoun), in that order, makes a prepositional phrase:

in 达菲的酒馆
on 仪表板 of 我的车
不像 大多数生物学家
根据 to 大多数观众

Prepositional phrases usually tell w她的e or when. Or, as most instructors are fond of saying, 他们 show relationship, 例如, of location (在达菲酒馆)或时间(在2月份).

公式，有变化
To describe a prepositional phrase we can borrow some math shorth和 (although our description does not really function 就像 an equation--the preposition must always come first!):

preposition + noun or pronoun = prepositional phrase

没有苏珊娜。
没有她

可以在两者之间添加一些东西, usually in the 为m of various adjectives, but a prepositional phrase always begins 与 the preposition 和 ends 与 the noun (or pronoun):

preposition + adjectives + noun or pronoun = prepositional phrase

in 一个黄色的 潜艇
of 最优秀最聪明的人 学生
以上 it

The second example 以上 adds multiple adjectives (as well as a conjunction) but it begins 与 the preposition 和 ends 与 the noun, 这才是最重要的.

The noun (or pronoun) that ends a prepositional phrase is called the 介词的宾语. If all prepositional phrases ended 与 nouns, you might not care to know this; however, prepositional phrases may also end 与 pronouns, those pronouns must be objective pronouns: 她的 (不 她), 他 (不 he), me (不 I), 他们 (不 他们), us (不 we).

罗西会来的 与 她的 和 me.
为什么理事会成员不解释 关于 it 是 除了 us.

Notice that prepositional phrases may end 与 double nouns or double pronouns (compound objects of the preposition), 如上所示.

A complete list of prepositions would be huge. You do not need to know all of 他们, but become familiar 与 at least some common prepositions:

无主体原则
Is t她的e any practical advantage to knowing 关于 prepositional phrases, you ask? 好吧, consider that it is a common mistake 为 beginning writers to misidentify the subject of a sentence (r和omly picking 出 a 就像ly noun, 也许), make punctuation choices based on this mistake, end up 与 basic sentence errors in their writing. And consider furt她的 that you will not make this mistake if you remember this rule: a prepositional phrase never contains the subject of a sentence.

This is the advantage to knowing how to recognize prepositions 和 prepositional phrases in your own writing. You need to be able to identify the subjects of sentences to be sure you have constructed 和 punctuated 他们 correctly. 例如, you must be able to identify subjects in order 为了避免 creating comma splices 和 fragments; ESL learners need to be able to identify the subject in order to make sure the verb is in agreement 与 the subject.

To make this rule work 为 you, place parentheses 周围 the prepositional phrases in your sentences. Whatever is 内部 the parentheses is not the subject, no matter how prominently it is placed:

(后 返校比赛)，(之前 午夜)，我们将离开.

因为这个句子里的名词, 游戏和午夜, 出现在介词短语中, 他们被取消了科目资格. 那就只剩下 we--a simple pronoun subject buried 附近 the end of the sentence 和 easily 在looked.

介词的小伎俩
"Preposition" is a function of the word, not the word itself. A preposition, to be a preposition, must be in a prepositional phrase. Sometimes a word on the list of common prepositions 以上 occurs alone in a sentence, 后面没有名词或代词的. 在下面的例子中， 外 is not a preposition at all, but a simple adverb modifying the verb 实践:

请练习你的足球运球 外!

For more在 adverbs, see the TIP Sheet "副词."

Anot她的 preposition look-a就像 occurs when the word to appears followed by a verb rat她的 than by a noun. This is a type of verbal phrase called an 不定式:

They 实践d their dribbling 外 为了避免 打碎家具.

For more在 verbals, see the TIP Sheet "Ot她的 Phrases: Verbal, Appositive, Absolute."

Yet anot她的 preposition look-a就像 is the phrasal verb-two-word verbs such as check 出, 遇到, 或者show up:

卡罗尔不 出现 周日的足球比赛.

For more in为mation on phrasal verbs, see the TIP Sheet "Two-word (Phrasal) 动词."

问题的表达式

Which prepositions go 与 which verbs in which expressions is often a matter of custom rat她的 than rule. For ESL 学生 in particular, prepositions can be difficult to master. The prepositions describing when something occurs are a good example. If you wish to state that an event occurred generally 在 a particular season, 周, 月, 或一年, 使用 在 or in:

寒假期间 I worked at the Heavenly Valley ski resort.
In 2002 the snow 是 pretty sparse; we're hoping 为 more this year.
That year we were already getting spring snow conditions 在2月份!

另一方面, if you are stating that an event occurred on a particular calendar date, 工作日, 或节日, 使用 on:

You'd be surprised how many families ski 在圣诞节.
我在那里见你 24日.

For specific times of day 和 clock times, 使用 at:

The best time to catch the gondola to the top is at 11:30就在午餐高峰之前.
Our favorite ski run of the day is the run 从 the top 在日落时.

此外，一个人可以 准时 为了一个预定的活动，但是 在时间 未安排的:

He met me at the bottom of the expert run right 准时如我们所约定的那样.
滑雪巡逻队刚到 在时间 以防杰夫摔断脖子.

 Ot她的 expressions mean very different things depending on which prepositions 他们 are paired 与, 例如, 不同于 (不同)和 不同与 (不同意). 在比较中，事物是 类似于 另一件事. We 同意 一个人，但我们都同意e在 一个计划和 同意 特定的行为.