It turned out that Zero was indeed seriously learning from humans. It even learned how to say things like "no can do" and "no good."
However, Ren Xiaosu was thinking that since Zero was "born" in the Wang Consortium, and now that the Wang Consortium had started operating like a war machine, would this make Zero learn something bad?
Moreover, Zero had also mentioned something on the phone before. It said that humans were against other lifeforms, and that it had "seen" the death of the creeper vine with its own eyes since its birth.
During the disaster at Stronghold 61, humans attacked the creeper vine with firearms, causing it to attack back madly. Immediately after, humans nipped the creeper vine in the bud just as it had gained sapience.
Ren Xiaosu had explained before that this was because the creeper vine had hurt humans. However, Zero said that it had also hurt humans before.