B. Use the Present Perfect Continuous

10. The vegetables have been boiling since 10 o'clock. 11. He has been waiting for her answer for six months. 12. My sister has been sending job applications for 3 months. 13. I have been trying to find my documents since last Sunday. 14. They have been learning Japanese for a couple of years. 15. My brother has been playing computer games for 3 hours.