learn the rule
where / wear / were / we're
where is an interrogative or relative adverb, indicating in or to what place or position.
- Where are you going?
- Your potato is where you left it.
wear is a verb meaning to have something on the body (clothing, accessories), or to erode something over time. It can also be a noun referring to clothing.
- What clothes do you like to wear?
- How does he wear his moustache?
- Over time the rock will wear away.
- evening wear, casual wear (noun form)
were is the plural past tense of to be. It refers to something that happened in the past for a group.
- We were looking for the potato.
- They were here yesterday.
we're is a contraction of we are. It's the plural present tense of to be, referring to something happening now or in the future for a group.
- We're all in this together.
- We're going to learn the rules.
- We're all really ugly.
- We're going to learn the rules so we're not so ugly.
None of the four are interchangeable.
When in doubt, try expanding we're to "we are". If that works, it's the contraction. Were is always past tense.
Where it goes wrong, we're noticing. You were warned. Now you look stupid. And ugly.