Here are a few beginnings for sentences that shouldn't exist.
1) I have grown up a lot.
This should be plain obvious through your actions. If you need to point it out in an effort to make people realise then maybe it just isn't that obvious.
2) Here is something funny & variations
It is really just one big let down from the very beginning. If something is funny part of the humour comes from the build up anyway so you have spoiled the climax before it has even occured. Or it just isn't funny and turns out to be a bigger let down.
3) I am different & variations of self professed eccentricity and individuality.
If you are odd that is ok, most people will figure this out on there own without being told and if they need to be told, maybe you are just not that much of an individual or and odd ball.
There are plenty more. But the majority of them are things that people will be able to work out for themselves, so why not let them? It it is like being told the answer to a riddle. I hate spoilers.