How to use verizon sim card with verizon iphone 4?

My htc windows phone 8x recently broke and i have been without a phone for a while now. Just yesterday my mom upgraded her iphone 4 to the iphone 4s. I'm wondering if its possible to use the sim card from my old phone to use my moms old iphone, if so, how?

Yawns…

call verizon… Activate i4 on your number… Pop in sim if needed… Have a beer… Enjoy

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No. Your 8x is a 4G phone, which needs a 4G LTE SIM card for use in the US Your iPhone 4s is a 3G phone, which has a global GSM SIM card for use internationally. The LTE SIM card will not work in the CDMA phone.

But, you can call Verizon to activate the iPhone on your line.

(btw, if it were possible, how would be easy. Take out of old phone, put in new phone.)