Sure, I can help you with that. Let's go through each sentence and find the mistakes in the underlined parts. 1. If you don't study your mathematics, you can't be able to do the exercises. The mistake is in part C. "can't be able" should be changed to "won't be able." 2. My niece can read by the time she was four years old. The mistake is in part C. "by the time" should be changed to "when." 3. Most ants could lift objects that are ten times heavier than their own bodies. There is no mistake in this sentence. 4. Tom won't be able to working in the shed because he is ill. The mistake is in part D. "to working" should be changed to "to work." 5. Bob was in an accident, but he won't be able to remember how he had hurt himself. The mistake is in part D. "how he had hurt himself" should be changed to "how he hurt himself." 6. That's my sister over there. She stands next to the window. The mistake is in part B. "stands" should be changed to "is standing." 7. Tom can't listen to music because his CD player was broken. The mistake is in part D. "was broken" should be changed to "is broken." 8. We couldn't hear the teacher because the students was very noisy. The mistake is in part C. "students was" should be changed to "students were." 9. Robots can work everywhere on the world, including on the seabed or in a volcano. The mistake is in part A. "everywhere on" should be changed to "anywhere in." I hope this helps! Let me know if you have any other questions about these sentences or anything else related to English language learning!