Quick answer: use sang for the simple past (She sang beautifully) and sung after has, have, had or in passive sentences (She has sung that song before).
Sing, Sang, Sung
Sing is an irregular verb. It does not add “-ed” to form the past. Instead the vowel changes: sing becomes sang in the simple past and sung as the past participle. This three-step change is shared by drink, ring, swim and begin.
When to Use Sang
Pick sang for a completed action in the past when no helping verb is used.
- The choir sang at the school festival.
- He sang in the shower this morning.
- We sang happy birthday to my sister.
When to Use Sung
Pick sung when the verb follows a helper. This covers the perfect tenses and the passive voice.
- She has sung in three countries.
- They had sung the anthem before the match began.
- The song was sung by thousands of fans.
The Helper Rule
The easiest check is to ask: is there a form of have or be right before the verb? If yes, you need sung. If the verb comes straight after the subject, you need sang. For example, “I sang” is correct, and “I have sung” is correct. Writing “I have sang” or “I sung” for a past event is a common error, even though you may hear it in casual speech or song lyrics.
Sung as a Part of Other Words
The form shows up in compound words as well. “Unsung heroes” are people whose work has not been praised enough. “Well-sung” describes a performance done skillfully. In these, sung works like an adjective formed from the participle.
Mistakes to Avoid
| Incorrect | Correct |
|---|---|
| He has sang for years. | He has sung for years. |
| She sung at the wedding. | She sang at the wedding. |
| We had sang together before. | We had sung together before. |
Memory Trick
Link the vowels to time. “A” is the quick answer to “what did you do?” so sang goes with simple past. “U” sounds like “you have”, which reminds you that sung needs have or had in front.
Try It Yourself
- Last night the band (sang / sung) their new single.
- Have you ever (sang / sung) on a stage?
- The lullaby was (sang / sung) softly.
Answers: sang, sung, sung.
Final Thoughts
Sang stands alone and sung leans on a helper. Once you notice the word in front of the verb, the correct form is usually obvious, and your writing will sound more polished.
