We still tend _ think chewing gum is a fairly recent invention, even _ there is evidence it was used 5,000 years ago in Finland.
to/though
25
The Ancient Greeks also chewed gum, as __ the Aztecs in Mexico during the sixteenth century.
did
15
As far as we know, however, it wasn’t __1869 that chewing gum became popular in its present form, __ New York inventor called Thomas Adams first had the idea of adding flavour to it.
until (till)/when
25
Nowadays, of course, it is chewed around the world, __ the fact that it continues to be regarded by some __ an unpleasant habit.
despite/as
25
Unfortunately, far too many people drop used gum onto the pavement, __ it remains for some time because it is extremely difficult to remove once it has stuck to the surface.
where
15
On the other hand, those _ favour of chewing gum claim it helps them relax, improves their concentration, and helps keep their teeth clean.
in
15
These days, most people are aware __ the environmental impact of motor vehicles, and they realise that cars are responsible __ many of the problems facing their cities.
of/for
25
Not __ people, however, ever stop __ think about how much money they would save by switching from driving to cycling.
many/to
25
Cars cost a lot to buy, and __ other major investments such as houses, they quickly lose their value.
unlike
25
On __ of that, there are running costs such as repair bills, tax and insurance, all of __ seem to go up every year.
top/which
25
Bicycles, by contrast, are far __ expensive to purchase and maintain, do not require petrol and are easy to park.
less
15
And if a lot more people took up cycling, the government could spend less of the nation’s resources on roads, which at present their taxes help pay for __ they drive on them or not.
whether
15
Perth, __ Capital of the state-of Western Australia, has been described as one of the most remote cities __ Earth.
the/on
25
Founded in 1829 and named after Perth in Scotland, it grew rapidly in the late nineteenth century __ a result of the discovery of gold in the state.
as
15
Nowadays it has a population of around two million people, and many of __ were born outside Australia.
whom
15
This has led __ Perth becoming a culturally diverse city.