用手拍一拍對方嘅膊頭 (to pat on one's shoulder)
動詞Examples
佢細細力拍下我膊頭。
keoi5 sai3 sai3 lik6 paak3 haa5 ngo5 bok3 tau4
He pats on my shoulder lightly.
靠私交解決問題 (figuratively: to pull strings; to take advantage with the help of one's friends)
Examples
你爸爸識校長嘅,拍膊頭咪可以入呢間學校囉。
nei5 baa4 baa1 sik1 haau6 zoeng2 ge3, paak3 bok3 tau4 mai6 ho2 ji5 jap6 nei1 gaan1 hok6 haau6 lo1.
Your father knows the principal. You can use his connections to get into this school.