Common Mistakes : Can

modal verb

?DUBIOUS: Can you possibly send me an application form
?GOOD: Could you possibly send me an application form

.DUBIOUS: I’d be grateful if you can confirm whether you are coming
.GOOD: I’d be grateful if you could confirm whether you are coming

:To make a polite request, use could
?Could you pass the butter, please

.BAD: The next generation can fly to the moon for their holidays
.GOOD: The next generation will be able to fly to the moon for their holidays

:Use can to talk about someone’s present ability
.All our children can swim

:Use be able to to predict someone’s future ability
.You’ll never be able to swim if you don’t try