self-interested
adj.利己主义的，自我本位的;
例句:
1.
Today's debate is thoroughly self-interested.
今天的辩论是完全自私的。
2.
This is puzzling because self-interested children might be expected to behave in precisely the opposite way.
这实在是令人困惑，因为我们通常都认为自私的孩子可能会表现得正好相反。
3.
Instead, it evolved as a self-interested weapon to fend off competitors, even when that competition is, in fact, a strategy of collaboration.
然而却发展成避开竞争对手的自私武器，即便竞争的本质是一种合作的策略。
