Should you say-- It was a welcome tonic or it was a welcomed tonic?

Both are correct, with slightly different meanings. In "feedback is welcome," which is the most common usage, welcome is an adjective describing feedback. In "feedback is welcomed," welcomed is a...

Both, depending on the construction. As an adjective, it is welcome: You're welcome to try it, or You're welcome here for as long as you like. As a past participle of the verb to welcome, it is...

Both are correct with different meaning. In "Your suggestions are welcome at any time" welcome is an adjective. In "Your suggestions are welcomed by the committee" welcomed is the passive participle...

This depends on the context. You might say "Does your mother want a drink?" or "Do your homework" but to switch them would be incorrect.

Don't say anything that will get u imbarrased, and don't say too much information about yourself to the person unless they're your friend , and dont share too little. Then they'll think youre...