B4

Cars are a common sight on roads today, but that wasn't always true. Back in the days before the car was invented, the only personal means of transport were the horse and the bicycle.

(past simple passive, т.к. машина была изобретена в определённый момент в прошлом)

INVENT

B5

The first cars got their power from steam and gas, and had a maximum speed of around nine miles an hour.

(past simple, т.к. это случилось тогда в прошлом)

GET

B6

In Britain, there was a law stopping cars from going over twomiles an hour in towns.

(Participle I, “останавливающий”, подходит по смысловому контексту)

STOP

B7

At the end of the nineteenth century, cars started to use petrol and became much faster than they had been.

(степень сравнения)

FAST

B8

Very few people at that time said that cars would change the worldin the future.

(согласование времён)

CHANGES

B9

That is exactly what has happened, though, and since then we have built close to eighteen million miles of roads on the Earth.

(present perfect, т.к. построили и до сих пор стpoим)

BUILD

B10

Perhaps the biggest sign of the success of the car is the fact that there are over 800 million of them in the world.

(степень сравнения)

BIG

B11

However, having more cars on the road means more pollution, and that's a major worry for many people.

(present simple, т.к. это общее утверждение)

MEAN