I can buy the sony camcord if I pay the money in monthly installments.

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Is the sentence above correct? Would you let me know some other expressions?

The only thing to is capitalize the word "Sony" as it is a proper name. Could you explain exactly what you mean by "other expressions?" Do you mean other ways to say the same thing?

Thank yoiu for your help.

What about the follwoing?

I can buy the sony camcord if I pay the money on monthly installment.

As Sra said, the word "Sony" must be capitalized. The phrase "on monthly installment" isn't correct. You could say ". . . if I pay the money on a monthly installment plan" -- or -- ". . . if I pay the money in monthly installments."

Yes, the sentence "I can buy the Sony camcorder if I pay the money in monthly installments" is grammatically correct.

Here are some other expressions you can use to convey the same meaning:

1. I can purchase the Sony camcorder by making monthly payments.
2. If I agree to pay in monthly installments, I can buy the Sony camcorder.
3. I have the option to buy the Sony camcorder if I choose to pay in monthly installments.
4. By paying the money in monthly installments, I am capable of purchasing the Sony camcorder.

Remember, when discussing payment arrangements, it is important to clearly specify the terms and conditions to avoid any misunderstandings.