A. strengthen B. virtual C. swap D. why A. betray B. have to C. interest D. squall A. pyramid B. because C. clean-up D. least A. pocket money B. leave behind C. famous D. head teacher A. pick B. compare to C. all D. the day after tomorrow A. late B. school begins C. mark D. pace A. seminar B. fit C. next D. ecosystem A. understand B. sell out C. content D. terrifying A. disturb B. take off C. worry about D. regiment A. let B. in amazement C. sticker D. Mexico