php獲取 本月 本周 或者 下月 下周的 開始時間 結束時間

$now_time = =("Y-m-d", get_date(,='d',=0(=='d' = ('Y-m-d 00:00:00',(" day" = ("Y-m-d 23:59:59",(" day"(=='w'(!=0){ = ('Y-m-d',(" week" = ("Y-m-d 00:00:00",(" Sunday" = ("Y-m-d 23:59:59",(" -6 days"(=='m'(!=0){ = ('Y-m-d',(" months" = ("Y-m-01 00:00:00",( = ("Y-m-d 23:59:59",(" +1 month -1 day" (,   = get_date(,'d'   = get_date(,'d',-1 = get_date(,'w' = get_date(,'w',-1 = get_date(,'m' = get_date(,'m',-1 '<pre>'();
();
();
();
();
();
 '</pre>';