Please could you help me to create a Latin motto which means ‘I am, therefore I thank.’ I’ve thought of sum ergo laudo, but perhaps laudo is closer to ‘I praise’. I’m looking for a word with a nuance closer to ‘I give thanks’ or ‘I am thankful’ but, because this is for a motto, I should like to capture the meaning of ‘I thank’ in a single Latin verb. Am I correct in thinking that the word order in the motto would be sum + ergo + (the word you suggest)? Thanks so much!
There is no Latin verb that means "thank". There is the noun "thank", gratia, and you can "give thanks", agere gratias. Using this, you'd get sum ergo gratias ago.
But this might sound a little clumsy, so using laudare (which is more "to praise" than "to thank") is a decent option. Whether you value simplicity or accuracy more is a matter of taste. With laudare you'd get sum ergo laudo as you suggest.
bene facis, bene vocas, bene narras
Thus, you could say something like
sum ergo bene vocas
Later in the entry there is a suggestion bene alone can also be used, as also stated in the linked question.
PS: credit goes to the linked question for inspiration.