Hi,
Here are some suggestions. I've tried to change as little as possible.
1. Workers (this sentence has no main verb! Workers need...? ...lack...?) excellent literacy skills, which will enable them to easily assimilate in-depth knowledge and to state their views clearly on specific issues.
2. Reading skills can decide whether a worker will be able to soak up lots of knowledge in a short time, and can help him to attain his goal of becoming a distinguished executive in the cutthroat business world.
3 It is inevitable that bad-tempered consumers will complain about a defective product in person, yet this situation may prevent them from having their complaints dealt with. After all, the more anger consumers show, the fewer problems they will be able to resolve.
Best wishes, Clive