orale database conversion to_char time in English

First, the Chinese display Sunday

select to_char(sysdate,'day','NLS_DATE_LANGUAGE=''SIMPLIFIED CHINESE''') from dual;

Second, the English display Sunday

select to_char(sysdate,'day','nls_date_language=american') from dual;

Third, the Chinese display month

select to_char(sysdate,'month','NLS_DATE_LANGUAGE=''SIMPLIFIED CHINESE''') from dual;

Fourth, the English display month

select to_char(sysdate,'month','nls_date_language=american') from dual;