public String toStringNormal() {
		return String.format("%04d-%02d-%02d", this.year,
				isLeapMonth() ? this.month - 1 : this.month, this.day);
	}
@Test
	public void toStringNormalTest(){
		ChineseDate date = new ChineseDate(DateUtil.parseDate("2020-03-1"));
		assertEquals("2020-02-08", date.toStringNormal());
	}