which ones would be the foreign and Primary Keys in the following:

CLIENTS $($ClientID$,$ ClientName, ClientAddress$)$

ENGAGEMENTS $($EngageID$,$ EngageTypeID, ClientID, EngageManagerID, EngageFee$)--->$main table

Engagetype$($engagetypeid$,$ description$)$

ENGAGEACCOUNTANT$($engageID$,$ acctID, hours, billable hours$)$

ACCOUNTANTS $($AcctID$,$ AcctName, BillingRate$)$

CERTIFICATIONS $($CertificationCode $,$ Description$)$

ACCOUNTANT$\_$CERTIFICATIONS $($AcctID$,$ CertificationCode$)$