| Answer | Crossword Clue |
|---|---|
| SNAPTO | Suddenly become alert |
| SITUP | Become suddenly alert: Colloq. |
| SATUP | Became suddenly alert |
| SITUP | Become alert |
| SNAPTO | Become suddenly aware |
| FIREUP | Become suddenly angry. |
| SNAPTO | Become suddenly attentive |
| TURNON | Become suddenly hostile to |
| FLARE | Become suddenly angry (with "up"). |
| NOVAS | They suddenly become much brighter |
| NOVAS | Stars that suddenly become much brighter |
