Sat Times Jumbo 978 ( cryptic)

[jimmywhiskers]

Absolutely stuck on the last two . Help please ! 21A Shrubs and things for adders to swallow placed centrally ( 6) . S?M?C? Is it SAMECH and why? 5D Following trips abroad , love endless sparkling wine (8) S?R?T?E . Also , 35A Spin renders pointless ,maybe what offenders did?(6) .Is it SPITED and why ?

[bert_h]

trips abroad = SPRIT, love endlessly = ZER(O), sparkling wine = SPRIT-ZER.

[Dinkypuzzled]

21a. sum(ac)s.

[Dinkypuzzled]

5d. sprit zer(o)

[shooty]

SPI = spin minus the N(orth)
TED = teds minus the S(outh)

(teds = renders)

[jimmywhiskers]

Many thanks folks .