I always try to (do something)

You use this phrase to describe something that you do because you think it's a good idea, but sometimes you aren't able to do it. Why not? Maybe because you forget, because you get too busy to do it, or because you don't have enough self control.

I always try to eat fresh fruit and vegetables, but it's hard on weekdays.

pay off (a bill)

When you "pay something off", it means that you completely pay for it. This is mostly used to talk about bill and loan payments. When you "pay off" a loan, it means that you have completely paid all of the money you borrowed, plus the loan's interest.

To "pay off" a credit card means to pay off all of the money that you spent on that credit card for the month.

Credit cards in the U.S. have a minimum payment that you have to pay each month. However, if you only pay the minimum, you will be charged interest for whatever amount hasn't been paid. If you "pay off" your credit card each month by the deadline, you won't be charged for interest.

a (credit card) bill

The word "bill" can refer to two things: 1) The piece of paper or the e-mail that a service sends you to tell you how much you need to pay them. 2) The amount of money that you have to pay.

So you can talk about the physical bill itself:

I put the phone bill over there on the counter, but now I can't find it.

Of you can talk about the amount of the bill. To describe the amount, use "high" and "low":

Our gas bills are pretty low.

As you can see from the last example, you can identify bills for different services. Some common ones are:

• electric bill
• phone bill
• cable bill
• Internet bill
• dry cleaning bill

You can also say the name of the company that's charging you:

This month's Time Warner bill was higher than last month's.