The phrase "knew for certain" is spelled as /n(j)u fɔː(r) ˈsɜːtn̩/. The word "knew" is spelled with "k" and "ew" which represents the /n(j)u/ sound. The word "for" is spelled as "f-o-r" which represents the /fɔː(r)/ sound. The word "certain" is spelled as "c-e-r-t-a-i-n" however, the phonetic transcription shows it as /ˈsɜːtn̩/ which represents the pronunciation of this word. It's important to keep in mind the correct spelling when writing and the correct pronunciation when speaking.
Knew for certain is a phrase that refers to having absolute or undeniable knowledge or certainty about something. When someone says they "knew for certain," they are expressing a high level of confidence in the accuracy or truthfulness of their knowledge. It implies that they are completely convinced and have no doubt about the fact or information they possess.
To know for certain means to have reliable evidence or information that substantiates one's beliefs or claims. It indicates that the knowledge or understanding is not based on assumptions or guesses but is firmly grounded in facts or evidence.
This expression often implies that the knowledge has been acquired through a trustworthy source or reliable means such as personal experience, direct observation, rigorous investigation, or the validation of credible sources. It suggests that there is no room for doubt or ambiguity and the certainty is based on irrefutable evidence.
When someone states they "knew for certain," they are emphasising the confidence and certainty they have regarding the information they possess. It conveys a strong conviction that the knowledge is accurate and reliable, leaving little to no room for skepticism or questioning.