Focus on the pronunciation of nail sth down
English definition of “nail sth down”
nail sth down — Phrasal Verb with nail
/neɪl/ verb [T] informal
› to agree the details of a decision, an agreement, etc. so that something can happen: The decision of who would be appointed Chief Executive was made months before the other terms of the merger were nailed down. The government hopes to nail down a deal with China by year's end.