in january还是on?还有My family usually clean(clean要不要加s,为什么)the house.

是On January还是In January JANUARY 用IN还是ON in january还是on?还有My family usually clean(clean要不要加s,为什么)the house. 是on January,2010还是in January,2010? 是In January 1,1999还是On January 1,1999 January.1699前面用in,还是on my brother was born （ ） the morning of January 1 用in还是on? On January 2011对吗?是用on 还是in? His birthday is-----------------january,中间是in还是on, in stock on january 16, 月份前用的是什么 介词 in 还是 onI was born on January eleventh.It's so cold in January. My birthday is （ ） January and peter's birthday is （ ） March 26th在括号内填in on at 还是for 或不填 英语翻译应该是In 1943 January还是In January ,1943 为什么? My birthday is on January ninth对吗? on January还是in January,前面用什么借此,还有就是年份（如new year、2009年）前面用什么借词,时间（如8 o'clock）前面用什么借词,星期几（Monday）前面用什么借词,还有at和in、on怎么区分?具体点! in my left 还是on my left? on my life 还是in my life? in my studies还是on my studies