Compared with cars，bicycles have several advantages besides being affordable.Firstly，they do not consume natural resources of petroleum.Secondly，they do not cause the pollution st but not least，they contribute to people’s health by giving them due physical

exercise.

2.句型

1）状语从句（时间，原因，地点，条件，让步，转折when, since, because, if, though, before等）

When the man is enjoying the cigarette, the smoke becomes a monster （怪物）which will devour him.

Whatever the reason, there are still some problems with student use of computers.

2倒装句（only, neither, nor, at no time, in no case)

Only through these measures can we hope to solve the problem.

Scattered around the globe are more than 100 small regions of isolated volcanic

activity known to geologists as hot spots.

3）被动句

Some measures should be taken to deal with the problem.

He is said to have accomplished a lot of great deeds.

Many people believe that…（It is believed that…）

4）强调句

It is not who rules us that is important , but how he rules us.

5) no more …than…

A home without love is no more a home than a body without a soul is a man.

6) may as well…as 与其…不如

One may as well not know a thing at all as know it imperfectly.

7）cannot…too…

You cannot be too careful.

8）否定+until(till)