Hi ynk,
If you are aware that Sentence Correction is your most glaring verbal weakness, you might first consider analyzing each incorrect Sentence Correction question from your most recent CAT. When analyzing each question, be sure to determine the particular grammar rule(s) that you overlooked: pronouns, subject/verb agreement, comparisons, modifiers, idioms, etc. Once you complete your analysis, go back and review your notes from your weakest topics.
After your review, consider doing some more focused SC practice, to find and fix any remaining weak areas. To help increase your verbal score even higher, it may be a good idea to follow a similar routine for Critical Reasoning and Reading Comprehension.
Once your weakest verbal areas have been addressed, you may want to take another few practice exams to track your progress. As above, once complete, analyze your mistakes and figure out remedies for them. Since your test is one week away you may consider taking another practice exam over the weekend and a final practice exam early next week. You could take the remaining exam from exam pack 1 and then the first exam from exam pack 2.
When taking the exam, try to replicate the test day experience as much as possible: Go to the library instead of taking the test in your house or apartment. Be sure to complete all sections (AWA, IR, Quant, and Verbal). Only take the allotted breaks.
Once you take your next CAT, report back with the results. I’m around to answer any further questions.