| Answer | Crossword Clue |
|---|---|
| HIVE | Place of intense activity |
| OVERDRIVE | Intense state of activity |
| fevers | state of heightened or intense emotion or activity |
| ferments | be in a state of agitation or intense activity |
| starburst | A period of intense activity in a galaxy involving the formation of stars |
| starbursts | A period of intense activity in a galaxy involving the formation of stars |
| fartlek | training technique, used esp. among runners, consisting of bursts of intense effort loosely alternating with less strenuous activity |
