Today's practice.

1. I'm up here with his lies        I've had it up to here with his lies

2. I'm up here with your attitude towards me            I've had it up to here with your attitude towards me.

3. I can't help but think you talk behind me.                I can't help but think you talk behind my back.

4. I can't help but think I fall back on English.            Correct

5. For the sake of my conscience, I said it.                Correct

6. For the sake of my conscience, I fessed up            Correct (more informal)

7. Please don't dismantle our relationship.                Correct

8.It is such a dime a dozen                                            You usually hear this phrase describing something plural.  So I would correct to "They're a dime a dozen".   And for some reason the word "such" just doesn't sound like it belongs here. 

9. Those faces are a dime a dozen.                            Grammatically correct, but the sentence doesn't make sense....you can't buy faces, so it is a strange comparison to use this expression (which means something is cheap and widely available/easy to get a hold of.)

10. It's dime a dozen.                                                   They're a dime a dozen.  Same explanation as #8

Good job with your practice!  I hope this helps!

1. I'm up to here with his lies

2. I'm up to here with your attitude towards me

3. I can't help but think you talk behind my back me.

4. I can't help but think I would fall back on my English.

5. For the sake of my conscience, I said it.

6. For the sake of my conscience, I fessed up

7. Please don't dismantle/mess up/take apart/ruin our relationship.

8.Its a dime a dozen.

9. Those faces are a dime a dozen.

10. It's a dime a dozen.