When making comparisons, “either” goes with “or” and “neither” with “nor”: “I want to buy either a new desktop computer or a laptop, but I have neither the cash nor the credit I need.”

“Either” often gets misplaced in a sentence: “He either wanted to build a gambling casino or a convent” should be “He wanted to build either a gambling casino or a convent.” In this example, both things are wanted, so “either” comes after the verb.

But if the action is different in regard to the things compared, the “either” has to come before the verb: “He wanted either to build a casino or remodel a convent.” Here two different actions are being compared, so the “either” has to precede both actions.