on the latch

(of a door or gate) closed but not locked

（門）關著但沒鎖上

let yourself in, the door's on the latch.

你進來吧，門沒鎖。

latch on

(of a breastfeeding baby) manage to get its mouth into the correct position around the nipple

（哺乳嬰兒）用嘴叼到乳頭

latch on to informal 非正式

attach oneself to (someone) as a constant and usually unwelcome companion

糾纏

he spent the whole evening trying to latch on to my friends.

他整個晚上都糾纏著我的朋友。

understand the meaning of (something)

理解，明白

[with clause]she'll soon latch on to what is happening.

她很快就會理解發生了什么。

latch on to 或 latch onto

To get hold of; obtain

取得；得到

latched on to a fortune in the fur trade.

在皮毛生意中賺了一大筆錢