Mental state predicates and adverbs

[Gloria Cappelli]

Dear Colleagues,


I am wondering whether sentences like

"I think that Paul has probably lost his keys" and
"I think that Paul has maybe lost his keys"

are totally acceptable in English, and if not why.
And what about:

"I think that Paul has certainly lost his keys"?

Does the cooccurrence with other verbs like "suppose", "guess", "assume",
etc. make a difference?

Moreover, I was wondering what makes

"It is certainly possible that he is at home"

fine and

"It is certainly probable that he is at home"

unacceptable.

Thank you in advance for your attention and for your help,

Gloria