本句中fined for speaking on their mobile phones while driving过去分词短语作定语修饰people.

4. ...young children who may not look before stepping into the road.

本句为倒装句，当表地点的介词短语在句首并且主语为代词时，句子全部倒状

At the gate lay a solider in uniform.

Behind our school runs a small river.

5. Some cyclists make the assumption that traffic laws do not apply to them, ...

make the assumption that =assume that... = think that ...

apply to 适用于 The rule _______ everyone. 此规则适用于任何人

apply A to B 把A运用于B

apply to sb, for sth. 向某人申请某事

Apply oneself to sth. 致力于某事

6. it is up to all of us roads users to make sure that we avoid accidents by paying attention to road safety.

It is up to sb, to do sth. 由某人决定做某事 It is up to you to decide what to do next.

Be up to sth. 多达成，直到，可与某物相比，正在忙于做某事

EXERCISES:

1. Who is it up to _____ an experienced teacher to _____ their puzzles?

A. to call for; solve B. calling in; solve C. to call in; sole D. to call on; setting

2. He is not ______ the part of "Othello".

A. until B. in C. to D. up to

3. If you _____ yourself to the job in hand, you'll soon finish it.

A. request B. appeal C. apply D. claim

4. On the top of the hill _____ where I once visited the monk.

A. a temple stands B. stands a temple C. a temple stands there D. does a temple stand

5. A _______ may be given ____ means of flags, lights, and guns.

A. sign, by B. signal, in C. signal; by D. sign, in