How do I use negative prefixes?

Which sentence is correct in each pair?

1 a) The coach driver was very unpolite and unfriendly.



b) In fact the whole tour was quite unsatisfactory.

These prefixes give words a negative meaning: un-, im-, dis, mis- and non-.

The most common prefix is un-. Some words taking un- are:
unavailable, uncomfortable, unconditional, unconscious, unconvincing, undemanding, undoubtedly, unforgettable, unforgivable, unlimited, unnecessary, unoccupied, unpolluted, unprejudiced, unsatisfactory, unscheduled

in-is also a commonly-used prefix. Words taking in- are:
inadequate, inadvisable, inappropriate, incapable, incompetent, incomplete, inconvenient, ineffective, inexcusable, inexpensive, inexperienced, insecure, insufficient, intolerable

We use im- before words beginning with p and m:
impolite, impossible, impractical, improper, immature.

Words taking non- are: non-existent, non-native
Words taking mis- are: mislead, misunderstand
Words taking dis- are: discourage, disobedient, disorganised, dissatisfied.

We say unsatisfactory (adj), but dissatisfaction (noun) and dissatisfied (adj).

Complete each sentence with a negative form of the word in brackets.

1. The College canteen is
   _____
   inadequate
   and needs to be improved. (adequate)
2. You
   _____
   misunderstood
   my meaning or you wouldn't have taken offence. (understand)
3. I don't accept that my behaviour was in any way
   _____
   improper
   (proper)
4. I'm writing to express my
   _____
   dissatisfaction
   with your firm. (satisfy)
5. We're most unhappy with the
   _____
   unsatisfactory
   service you provided. (satisfy)
6. I'm afraid your report is
   _____
   incomplete
   . (complete)
7. For a
   _____
   non-native
   speaker your pronunciation is excellent. (native)
8. Thank you for a(n)
   _____
   unforgettable
   holiday. (forget)