For example, the query below will simply cause the error in title:
SELECT * from tbl SELECT;
line 1:15: mismatched input 'SELECT'. Expecting: '(', 'LATERAL', 'UNNEST', <identifier>
A keyword is detected in SQL, while it should not be there as per SQL grammar. As result a compile error as titled, will be output.
Locate the keyword by information in error message (in this case 'line 1:15'), then check and fix it.
SELECT * from tbl;