( ( For ( multicellular organisms ) ) ( , ( apoptosis ( ( is ( ( an ( efficient way ) ) ( of ( eliminating ( cells ( which ( have ( been ( infected ( by ( a virus ) ) ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (PP (IN For) (NP (NN multicellular) (NNS organisms))) (, ,) (NP (NNS apoptosis)) (VP (VBZ is) (NP (NP (DT an) (JJ efficient) (NN way)) (PP (IN of) (S (VP (VBG eliminating) (NP (NP (NNS cells)) (SBAR (WHNP (WDT which)) (S (VP (VBP have) (VP (VBN been) (VP (VBN infected) (PP (IN by) (NP (DT a) (NN virus)))))))))))))) (. .)))
For multicellular organisms, apoptosis is an efficient way of eliminating cells which have been infected by a virus.
(ROOT (S (S (NP (JJ Single-celled) (NNS organisms) (CC and) (NN multicellular) (NNS organisms)) (VP (VBP have) (NP (NP (DT this)) (PP (IN in) (NP (JJ common)))))) (: :) (S (NP (DT both)) (VP (VBP have) (NP (DT a) (NN way) (S (VP (TO to) (VP (VB get) (ADJP (JJ rid)) (PP (IN of) (NP (NN waste) (NNS materials))))))))) (. .)))