我想用多个条件查询联接两个表

string sql = "Select l.*, c.FirstName_CompanyName from dbo.Loan l left join Customer c on  l.CustId=c.CustId where LoanAccountNo > 0 ";

当我实现上面的代码，但我发现我需要过滤贷款表批准和删除，但我似乎不能得到它的权利。
下面的代码是我尝试过但不起作用的代码

string sql = "Select l.*, c.FirstName_CompanyName from dbo.Loan WHERE Delete = 0 AND Approve = 1 l left join Customer c on  l.CustId=c.CustId where LoanAccountNo > 0 ";

{"Incorrect syntax near the keyword 'Delete'."}