[ wúxiào ] of no avail; to no avail; invalid; null and void; nullity (合同等的); in vain; unavailability; ineffectiveness; inefficiency; futility; flop 短语和例子 宣布选举无效 nullify an election; 医治无效 fail to respond to medical treatment; 宣布决定无效 declare decision invalid; 无效的契约 an invalid contract; 无效投资 make the investment inefficient; 无效法律行为 nullity of juristic act; 无效分蘖 [农业] ineffective tillering; 无效功 lost work; 无效合同 invalid contract; 无效劳动 lost labour (in agricultural production); 无效期 adynamic stage; 无效诉讼 annulment suit; 无效条款 irritancy; 无效约因 infirmative consideration