Parallelism CH4, P12

[nikhilgupta08]

Tobacco Companies, shaken by string of legal setback in United States, but which retain strong growth prospects in developing world, face an uncertain future.

Solution in book - Tobacco Companies, which have been shaken by string of legal setback in United States, but which retain strong growth prospects in developing world, face an uncertain future.

If I write it like below;

Tobacco Companies, which are shaken by string of legal setback in United States, but which retain strong growth prospects in developing world, face an uncertain future.

Will it be correct, If yes why, if not why?

Thanks for your help in advance.

Regards,
Nikhil

[jlucero]

From a parallelism standpoint, yes. From a meaning standpoint, no. Have been shaken is better here than are shaken to express the true meaning of the sentence- that something started in the past and continues through now. However, the parallelism and usage of your verb is acceptable if the verb were better expressed as present tense:

Tobacco Companies, which are weaker (now) than ever, but which retain (now) strong growth prospects in developing world, face an uncertain future.

Tobacco Companies, which have been shaken (over the last few years) by string of legal setback in United States, but which retain strong growth prospects in developing world, face an uncertain future.