1) You____________(must / can) drive carefully near the crossing.
2) The water____________(was able to / couldn’t) be cold. It has been very hot
these days.
3) The elephants______________(mustn’t / are not able to) stand the mice.
4) My Granny____________(could / mustn’t) speak several languages.
5) People____________(mustn’t / are not able to) litter in the city.

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