When speaking to your boss you should always maintain a level of professionalism—saying the wrong thing could really do some damage to your career.

1.Don't say: "No, I don’t have the time"

When your boss asks you to do something there is never a reason for you to ever answer with the word, "no". Even if you are super busy with other projects and you really feel that you don’t have adequate time to do it all, ask your boss to help you prioritize which task you should do first. That way you look like an employee that has a ‘can’t do attitude’ but one with a ‘can do attitude’.

2.Don't say: "It wasn’t my fault: It’s so-and so’s fault."

Playing the blame game is a treacherous road to go down and it’s childish. If you are innocent then explain to your boss why. You should never throw any of your co-workers under the bus, especially if you may be at fault. If your boss sees that you’re frequently pointing the finger at some point they may wonder who really is to blame.

3.Don't say: "I’m looking for a new job"

Of course employers know that any given time a person from their staff could be searching for new work, but there’s a big difference in your boss thinking you may be looking and knowing that you’re looking. In a perfect world you should be able to let your boss know that you are actively seeking new work; however most bosses will take this as a slap in the face. It’s better to give them your two weeks notice when you do find that new job.

4.Don't say: "I don’t know how to do that"

If you boss asks you to do something, and you’re not sure exactly how to do it, you definitely should not let on that you are clueless. Instead, ask her for direction on how to get started (i.e., is there a co-worker who can teach you? An online tutorial you could follow?) This shows that you’re ready and willing to learn, without admitting outright ignorance.

5.Don't say: "I’m broke. I need a raise"

It’s not that you should never ask your boss for a raise, but don’t go into salary negotiations talking about needing more money because of your financial woes. Your boss won’t be swayed. When you do ask for a raise, be armed with evidence of your achievements in the work place and keep your personal life out of the equation.

6.Don't say: The old boss didn’t do it this way

You wouldn’t want to be compared to an ex-coworker in your new position, and your new boss most likely feels the same. Also your boss may think that you are stuck in your ways, that you don’t adapt well to change, and aren’t flexible. This may lead to you being cut out of new projects or assignments because it appears that you can’t handle change.

7.Don't say: "It’s slow. I'm leaving early today"

If you need to leave early for a doctor’s appointment, that’s one thing. But you should never ask your boss to leave early because you don’t have anything to do. Bosses like it when their employees show initiative so if there’s a lull in your day you should find out what new projects are on the horizon.

8.Don't say: "I’m bored"

You are being paid to be productive at work as well as remain enthusiastic and it’s not your boss’s responsibility to find a way to make your job more interesting. Instead of saying, "I’m bored," volunteer to spearhead a new and interesting project or ask your boss for more responsibilities.

9.Don't say: "I’m so hungover"

If you have become close with your boss and have developed a friendly relationship, it may seem fine to you to tell them about all the fun you had last night, but it’s not. If this is happening frequently and you’re coming in five minutes late here and 10 minutes late there your boss may start to question if your partying has something to do with the lateness. At the end of the day you must remind yourself this is the person who makes the decisions about you receiving raises, promotions, and bonuses.