because it's associated with stone tools.因為他們擅于使用石制工具
associated with 與…相聯系,與 ... 有關
I associated with him in business.
我過去和他合伙經商。
He was briefly associated with that organization.
他同那個組織有過短時間的聯系。
and a smaller face that's tucked up under the skull.顱骨下方的臉 ,則變小了
tuck up掀起,折起,卷起
Please tuck up the chair and put it side.
請把椅子折起來放在一邊。
Please help me tuck up my sleeves.
請幫我卷起袖子。