動詞
向人打暗號畀提示 give hint to somebody with codes or signs that not regonizable normally, literally to send a message throught telegram.
上次考試全班冇人合到格，所以今次老師向學生打哂電報，提示佢哋要温邊題。
上次考试全班冇人合到格，所以今次老师向学生打哂电报，提示佢哋要温边题。
No one in the class can pass the last exam, so the teacher give the students hints in order to guide them for revision.
Definitions (Wiktionary)
verb, Wu
to flash amorous glances (syn.) 眉目傳情, 眉目传情