'Proper' is an adjective and so it doesn't have a past tense.
The past tense is termed.
Sneaked Is the original past tense form, but snuck is optional.
The correct past tense of "initial" is "initialed."
They have the past tense listed as texted.
Tanzania is a proper noun, not a verb tense.
Lacked. Eg. He lacked a proper education.
The proper grammatical past tense of find out is "found out." "I didn't need to use the internet to help me with my homework as I already found out the answer in my textbook earlier this afternoon" is a proper way to use found out in a sentence with past tense.
corrected
Welcomed
In which case there is no past tense, since it is a proper noun. What is the simple past tense of the verb win? The past tense is won.
wondered
Audited