Manyscientists have been probing psychologicalproblems.

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for; could have been with; should have been at; could have been from; may have been

have been in have been to have gone to have been

may have been; can’t have been must have been; mustn’t have been may have been; must have been must have been; mustn’t be

have gone to, have been to have been to, have gone to have gone to, have been in have been to, have been in

may not have been couldn’t have been mustn’t have been needn’t have been

She's always helpful. A. need have been could have been should have been must have been

he will have been will have he been will have been he will he have been

have been in have been to 　　 have gone to have been

might have been would have been should have been must have been

have;have has;has have been;have been has been;has been

can' t have been shouldn' t have been mustn't have been wouldn' t have been

have been would have been could have been should have

gone , have been hunting for been , have been hunted for been , have been hunting for gone , have been looking for

had been; could have been has been; couldn't have been had been; must have been has been; shouldn't have been

have been to ; have gone to have gone to ; have been to have been to ; went to went ; have been to

need have been avoided must have been avoided might have been avoided will have been avoided

To have been caught , a Have been caught , a To have been caught , / Have been caught . /

can't have been shouldn't have been mustn't have been wouldn't have been

need have been could have been should have been must have been

must have been couldn’t have been would have been should have been