青黄不接

qīng huáng bù jiē

a gap between the old and the new

Character by character

青qīng
green

黄huáng
yellow

不bù
not

接jiē
connect

老员工退休了，新人还没培养起来，青黄不接。

The veterans have retired and the newcomers aren't ready: there's a gap.

Tone: neutral.

The old grain (yellow) runs out before the new crop (green) ripens; now talent gaps too.

Learn it in context

This idiom and thousands more are in Learn Chinese with Bao, with audio, pinyin and drills that make them stick.