"In my day . . . "
One thing parents seem to find irresistible is using examples from their childhoods to make a case for why something should (or should not) be done and why something is (or is not) hard to do. "When I was a little girl, my father wouldn't let me . . . " "In my day we didn't watch TV after school, we did our homework."
It's hard for kids to relate to this history. Their reaction is likely to be much eye rolling, rather than giving any serious thought to what it was like when you were growing up; and when you say things like, "I'm doing it for your own good" or "You'll thank me for this some day", you have filled the air with words that have very little meaning.
More importantly, you have shifted the discussion and avoided giving any reasons for what you are saying. If there's a rule in the house that children must finish their homework before watching TV, be clear about the rule and don't hide behind cliches or stories of your past. Give your reasons and be open to a rational discussion with your child. Explain exactly why a rule exists. If children have an alternative plan, be open to trying their ideas for an agreed upon period of time. Have an understanding that you will discuss it again and decide which way worked best. This is a valuable learning experience. Never say "I told you so" if you go back to the original rule.
"It's not that tough to . . . "
Another common problem in talking with children and teenagers is communication that doesn't go far enough. For example, you may have agreed there is a certain job to do and who will do it; but you have not talked about when the job will be done. If Mom thinks her son is going to do a chore right away and he plans to do it after the baseball game . . . or next week . . . , they have a serious misunderstanding. When expectations are not clearly spelled out, parents must either remain frustrated in silence or engage in repeated nagging about the work not being done in a timely manner.
As you talk with your children and teenagers, approach them in a direct and forthright manner. Provide clear messages and explain the patterns of behavior you expect from them. Your youngsters will then respect you more and respond to your reasonable expectations in a healthier and more responsible way.