Bang, bash, belt, bump, criticize, damn, ping, rap, roast, smash, sock, strike, tap, and whack are synonyms for knock.
overall
Substances would work
I started to knock on the door. I will knock before I open the door.
It depends what kind of cold you are asking about. I would recommend searching a thesaurus: thesaurus.com is a place you could look.
2
you can use or , otherwise, or rather than.
Acquired, obtained, received, or gained are alternative words that can be used instead of "got."
a or an
Some alternative words to use instead of "he" include: they, it, the person, the individual, one.
Some alternatives to "as" include "since," "because," "while," and "given that."
traitor
like
Was the joke this instead? Knock, Knock! Who's there? Hop. Hop who? Hop, Hop, Away. - The Easter Bunny's gone!
instead of knock on wood, it can be knock on snow!
Instead of the phrase "freaked out", try:stunnedstartledalarmedpanicked
You could use words like us, we, our, ourselves.
smash