a person who is content and satisfied with life
人生に満足し、幸せを感じている人 (jinsei ni manzoku shi, shiawase o kanjite iru hito)
"After getting the job, he’s been a happy camper."
"仕事を得た後、彼はハッピーキャンパーです。" (shigoto o eta ato, kare wa **happī kyanpā** desu)
a friend you have known for a long time
to relax or slow down after activity
to start behaving in an unusual or uncontrolled way
feeling nervous or anxious
to win by a very large margin
to model the behavior you expect from others