Sometimes overly-used comments lean toward the hilarious...especially if you've channelled these words before. Just wait til your dad gets home. Beds are for sleeping, not for jumping. Eat your vegetables. Don't sit so close to the tv. Your face is going to freeze that way.
In a book, though, a cliche' can be downright irritating. While imitation may be a symptom of admiration, it can also be a sign of an under- developed plot or character. Here's a tip: If you can recognize your story in another's book or dialogue, take a step back and consider why this might be. Sometimes it's a case of admiration for another's work, and that's not a bad thing. But if it's because there is no inspiration on tap, lay down the pen and take a break.
Yes, I said it: take a break from writing. Get outdoors and enjoy nature. Gather with friends and get a game of charades going. Watch your children at play. Listen to whatever music inspires you. Soon the inspiration will come again and you'll find that the words will begin to flow. And they'll be your own words, from your own imagination..
And isn't that why we write?