"celebrate"
It is customary to Celebrate / Celebrating... is customary
"raise your hand"
It is customary to raise your hand... / Raising your hand is customary
"point fingers"
Is it rude to point fingers... / Pointing fingers is rude...
"starts a conversation"
It is customary to start a conversation... / Starting a conversation is customary...
"shake hands"
It is customary to shake hands... / Shaking hands is customary...
"tip"
It is cutomary to tip... / Tipping is customary...
"say please"
It is customary to say please... / Saying please is customary
"pay attention"
It is customary to pay attention... / Paying attention is customary
"bow"
It is customary to bow... / Bowing is customary ....
"eat with your mouth open"
It is rude to eat... / Eating .... is rude
"speak loudly"
It's rude to speak loudly.../ Speaking loudly..is rude ...