close in
(of days) gradually become shorter (指白天)渐渐变短
The days are closing in now that autumn is here. 秋天来到了, 白天渐渐短了. close in (on sb/sth)
(a) come nearer and attack from several directions 从四面八方逼近并攻击
The enemy is closing in (on us). 敌人从四面八方(向我们)逼近.
(b) surround or envelop sb/sth 围绕或笼罩某人[某事物]
Darkness was gradually closing in. 暮色渐渐降临.