A literal word-by-word translation would be 'id est vita'. However, when we use the words in English, we usually imply that 'life often goes awry', not turning out quite as we expect. So how about, 'Vitam praedicere nesciamus', which might mean 'We cannot predict life'?
My advice to you - based on past experience of questions involving Latin on AnswerBank - is to check with an 'expert' whatever answer(s) you get here...including mine! For example, if your local secondary school has a Classics Department or even just a solitary Latin teacher, try to get a response from him/her. An alternative is to approach a local Catholic priest.
If someone suggests an on-line translation site, I'd treat that with even more care than answers here. They are generally much too vague or even ridiculous, unless you are quite knowledgeable about the language in any case.