Using a mysqli prepared statement to select a random cell instead of MySQL? (to prevent sql injection)

Question

        $user_name = "name";
        $password = "password";
        $database = "words";
        $server = "host";

        $db_handle = mysql_connect($server, $user_name, $password) or die (mysql_error());
        $db_found = mysql_select_db($database, $db_handle) or die (mysql_error()); 

        $randVerb = mysql_query("SELECT * FROM verbs ORDER BY RAND() LIMIT 1"); 
        $db_field = mysql_fetch_assoc($randVerb); 
        $definition= $db_field['def']; 

I have read that to prevent SQL injection, all MySQL statements should actually my mysqli and parametered. The above code connects to a database, selects a random 'verbs' row, and then takes the cell that intersects the 'verb' row and the def column (the definition of that verb) using mysql_fetch_assoc.

How would this be converted to a mysqli piece of code safe from injection? Would I use mysql_fetch_assoc in mysqli?