我们可以不理会他而直接去找主席,但那样做我们就如履薄冰了。 We could ignore him and go direct to the chairman, but we'd be skating on very thin ice.
他似乎很满意我对机器操作的叙述,可是我却如履薄冰,因为我自己对那机器实在了解不多。 He seemed satisfied with my description of how the machine works, but I was skating on thin ice because I don't really know much about it myself.