There
is no difference in meaning and little or no difference in use.
Chemicals, gases or cloth materials that are flammable /
inflammable catch fire and burn easily. Perhaps, in usage,
cloth materials are usually described as inflammable. So
we might say: 'The material from which these car seats are made
is highly inflammable. And conversely, certain gases or chemicals
may be thought of as flammable. So we might say: 'Aircraft
fuel is highly flammable'. But there are no hard and fast patterns.
All this is somewhat strange, because usually when we add a prefix
such as in- or un- or dis- to the beginning
of adjectives, adverbs and verbs, we give them the opposite meaning.
Try
this activity. Draw half a dozen columns on a large piece of paper
and insert a prefix heading in each column. Perhaps leave one or two
columns empty for new prefix headings as they occur to you. Your piece
of paper should look something like this:
un-
im-
in-
il-
dis-
ir-
Then,
over a period of time, write in as many adjectives with a negative
meaning using these prefixes that you can think of.
To
help you get started, you might like to test your knowledge against
these opposites. Print out this exercise, fill in the missing words
and then check your answers against the answer key. The first one
is done for you.
Opposite
of:
happy:
We were really unhappy with the way the party
was going
legal:
There is no doubt that cannabis will remain an ______________
drug for the foreseeable future.
possible:
It was quite _________________ for us to drive all the way from
Paris to Madrid in one day.
successful:
He made an ________________ attempt to climb the highest mountain
in the range.
responsible:
To take the boat out with four children under the age of ten and
with no life jackets on board was quite ________________ of him.
appropriate:
The dress she was wearing was quite _________________ for the
occasion.
polite:
It was very ________________ of him to insult his mother in front
of his aunt.
religious:
They were a completely _________________ family and I never thought
that one day I would marry one of the daughters.
honest:
As a politician he was __________________ and it was not long
before nobody trusted him.
perfect:
The goods were ________________ and had to be returned to the
store we bought them from.
contented:
She was __________________ with her life and decided that things
had to change.
1. An illegal drug
2. Impossible to drive such a distance in one day
3. An unsuccessful attempt
4. Irresponsible behaviour
5. A dress which was inappropriate for the occasion
6. Impolite behaviour
7. An irreligious family
8. A dishonest politician
9. Imperfect goods
10. Discontented with her life
N.B.
As you complete your table, you will probably find that you end
up with many more adjectives in the un- and in- columns
than in any others. Happy hunting!
