How do you write the word reciprocate in a sentence?

Reciprocate means to give back something of equal or greater value. An example of this would be:

"Janie took me out for dinner, so I will reciprocate by taking her to the movies."

A Reciprocal arrangement is a trade. A reciprocal agreement is an agreement to make a trade.

Example: two people trade babysitting. One watches both sets of kids on Tuesday, and the other watches both sets on Wednesday.

Example: Senator Jones agrees to vote for Senator Smith's bill and Senator Smith agrees to vote for Senator Jones' bill.

Reciprocal arrangements do not include money. They are barters.