They were all started on one day , September 7th , 1947 , tocelebrate 800 years since the founding of Moscow .
他们于1947年9月7日开工，以庆祝莫斯科建城800周年。
Apple has sent out invites for a September 7th event where it is expected to unveil the iPhone 7 .
苹果公司发出了9月7日（发布会）的邀请函，揭开iPhone7的面纱。
September 7th