确保: to ensure, to guarantee...
势必: to be bound to, undoubtedly will...
船长: captain (of a boat), skipper...
纽扣: button...
净: clean, completely, only, net (income, exports etc), (Chinese opera) painted face male role...
专业: specialty, specialized field, main field of study (at university), major, professional...
秒: second (unit of time), arc second (angular measurement unit), (coll.) instantly...