cannot say boo to a goose

• vi. 胆小如鼠(羞怯)

例句

用作不及物动词 (vi.)

1. He remained a mouse in public affairs.
   在公众事务上他依然胆小如鼠。
2. He bellows like a bull, but is weak as a bulrush.
   气壮如牛，胆小如鼠。