The FDA recommended that anyone who had tested negative over a period of nearly six months ask their doctor whether they should be tested a second time.
美国食品管理局当时建议，测出阴性反应超过六个月的人应向医生咨询，确定是否需要再做一次测试。
2
Detection of the former general should visit a doctor who might have both positive and negative.
检测前医生一般应向就诊者说明可能产生的正反两方面的影响。
3
You should encourage her in her attempts to become a doctor, instead of being so negative about it.