1.       Types of Sentences

A. The periodic Sentence (掉尾句)

所谓掉尾句，是指只有读到句子末尾，才能明白整个句子意思的一种句子类型，掉尾句的修辞作用在于它一直吸引着读者或听众的注意力，句子不读完就得不到一个完整的概念。掉尾句一般都是一步步地扩展，一层层地升，在句末达到高潮，强调句子的主要意思给读者留下深刻的印象。有时，一个句子中间的某些地方也可以停顿，并且具有相对的语法结构完整性，但它仍不失为掉尾句，因为附加的成分或从句仍然吸引着读者的极大兴趣，读者希望知道后面还要讲些什么使用掉尾句时一定要使悬念自然、不生硬。使用过多或使用不当都会给人以矫揉造作之感。例如：

1.         Having passed the house every for two years, and knowing that the man was a cripple, I could believe what the next-door neighbor told me.

如果years或cripple之后停顿，语义和语法结构都不完整。只有读到句子末尾，才知道作者要讲什么。

LOOSE CONSTRUCTION（松散结构）是一种组织松弛的子，或叫松句（loose sentence）。它的组成部分可以比较自由地拆散，在句中的某些地方，可以随意停顿，而且语法上具有一定的完整性。松句的特点是：自然、轻松、流畅、易懂。例如：

He was sitting before the fire in a large armchair when we entered.

Notice the difference between the loose and periodic constructions in the following examples:

LOOSE CONSTRUCTION

  The history of English is the history of our civilization on many ways.

PERIODIC SENTENCE

  In many ways, the history of English words is the history of our civilization.

Practice

Rewrite the following sentences so that the final emphasis falls on the idea in the clause presented at the beginning of each sentence.

1．  The course was not very difficult, although I didn’t receive a high grade.

Although I didn’t receive a high grade, the course was not very difficult.

2.     We could not find the book in spite of our search.

3.     She decided to go on working though she was very tired.