How to make checkbox = true in rich text formula button?

I'm trying to add one more field into this rich text formula. It's a checkbox field that I'd like to be checked as true. When I try to add it and set the value as '1' I get syntax errors. How can I add a checkbox field to be set as true?

If([Check],
"<a " & $addstyle & " \" href='" & [_DBID_TASKS] & "?act=API_GenAddRecordForm&_fid_34=" & URLEncode ([PropertyAddress: Street 1])&
"_fid_35=" & URLEncode([PropertyAddress: Street 2])&
"_fid_36=" & URLEncode([PropertyAddress: City])&
"_fid_37=" & URLEncode([PropertyAddress: State/Region])&
"_fid_38=" & URLEncode([PropertyAddress: Postal Code])&
"_fid_32=" & URLEncode([PropertyAddress: Postal Code])&"&z=" & Rurl()& "'>Add Task</a>", "")


"<a " & $addstyle & " \" href='" & [_DBID_KNOCKS] & "?act=API_GenAddRecordForm&_fid_9=" & URLEncode ([Related Property Assignment])& "&z=" & Rurl()& "'>Add Outreach</a>")


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Raymond Sakar
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