Frequency: The word is one of the 1500 most common words in English.
1.
You use ~ to indicate that the information you are giving is something that you have heard, but you are not certain that it is true.
Oil prices fell this week to their lowest level in fourteen months, ~ because of over-production.
ADV: ADV with cl/group, ADV before v vagueness
2.
You use ~ to refer to something that seems to be true, although you are not sure whether it is or not.
The recent deterioration has been caused by an ~ endless recession...
ADV: ADV with cl/group, ADV before v