Helen wrote a novel. He made a cowboy film, too.

Root is used to describe two actions performed by the same subject

A. wrong structure. (Two components connected by “not only…but also …” must have the same form)

B. wrong structure (both ….. and…)

C. wrong meaning (either…or…: either this or that)

D. Inversion of words

S + not only + V1 + but also + V2 Not only + TĐT + S + V1 but (S) also + V2

Not only did Helen write a novel, he also produced a movie.