印象中有cut it in half的说法,in表方式,而不用into

cut into half 固定搭配 把什么切成两半.
cut in 主要是插嘴,插入的意思.
只有在以下情况下表示切成两半时用到cut in half
The melon was cut in half. 瓜被切成了两半. 此句拆为
the melon was cut/ in half. 并非cut in half短语.

是的,但是有
It was cut into three parts.
它被割成了三块。

in half表示两半,是固定搭配.而用into的话就需要接two,three,...parts或者pieces.