- NANOSECOND {NANO}{SECOND} 16 - Bear city transport with some bitterness (8) - ACERBITY * 17 - Extinct brute man with stood change (8) - MASTODON {MAN+STOOD}* 18 - The vehicle has l eft home with alien instrument (8) - CLARINET {C{L}AR}{IN}{ET} 22 - A cheap building material will change without