In the English Grammar Profile, B2 point 137 in MODALITY is defined as:

negative forms of ‘can’t’ and ‘cannot’ to guess, predict and deduce.

This point is an extremely difficult point to locate because it heavily relies on usage.  The use of ‘can’t’ is A1 by default, but not ‘cannot’ which has not been given a level in the EGP.  We can try to mimic the examples given by the EGP:

You look very pale and you can’t be feeling well.
I think that it can’t be true.
He can’t be; he is too young.
It cannot be any good.

However, none of our common clusters shows signs of guessing, predicting, but we could allow for ‘deducing’ in that there possibly seems to be an attempt to arrive at a conclusion.  They mostly still show high complexity regardless.

_p can|ca _xx be _j

1 I CA N’T BE SURE 1777

2 WE CANNOT BE RESPONSIBLE 1127

  Idaho EdNews

Nampa teachers ask for online-only start to the school year

“We cannot be responsible for putting our students, staff and families at risk if we have the opportunity and ability to avoid it,” Maine wrote.

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3 WE CAN NOT BE SURE 1056
4 WE CA N’T BE SURE 991

5 YOU CAN’T BE SURE 883

  Racing TV

Nassau Stakes: Donnacha O’Brien hopeful Fancy Blue will …

On her ability to act at the Sussex track, he said: “You can’t be sure until you go there, but she’s quite easy to ride in a race and adaptable.

6 WE CANNOT BE CERTAIN 609

7 YOU CAN NOT BE SURE 520

8 YOU CAN’T BE SERIOUS 494

9 I CAN NOT BE SURE 478
10 I CA N’T BE CERTAIN 419
11 IT CA N’T BE GOOD 293
12 WE CA N’T BE CERTAIN 270
13 IT CA N’T BE EASY 238
14 YOU CA N’T BE AFRAID 234
15 IT CAN NOT BE TRUE 214
16 I CAN NOT BE CERTAIN 210
17 IT CA N’T BE TRUE 202
18 YOU CAN NOT BE SERIOUS 182
19 YOU CA N’T BE CERTAIN 141
20 YOU CAN NOT BE CERTAIN 139

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