迟到

迟到 (chídào) means 'to arrive late' — typically to school, work, a meeting, or any scheduled event. It is a 'verb-result' compound: 迟 means 'late / delayed' and 到 means 'to arrive,' so literally 'to arrive late.' Two important things for English speakers: first, 迟到 describes the act of arriving late, not the state of being delayed in general — for a flight that is delayed, Chinese uses 晚点 (wǎndiǎn) or 延误 (yánwù), not 迟到.

Second, because 迟到 already contains the result 到 ('arrive'), you usually don't add 了 inside the word; instead you put 了 at the end: 我迟到了 ('I was late'), not 我迟了到. You can quantify how late by adding a time: 迟到十分钟 ('ten minutes late')