still-unknownCOCA²⁵⁴³³⁷⁺⁶BNC²³⁶²¹³⁺¹ 基本例句 🌏未知 The ancestor virus— which, like many diseases, may have crossed into simians from another, still-unknown species — may have existed for millions of years. 这种病毒的祖先——像其他病毒一样，可能是其他病毒的混合体，仍是一种未知的病毒——可能几百万年前就存在了。 yeeyan