INFabbr.步兵团(=infantry)abbr.不定式(=infinitive)abbr.中程核力量(=intermediate-range nuclear forces)Infron维生素D2[维生素类药]

1. Doctor is looking for the blood donor who can offer infrequence blood to the patient.
   医生正在寻找能给一个血型罕见的病人输血的献血者。
2. The doctors were overwhelmed by the infrequence of the illness, however they calmed down at once and they began to examine my husband.
   病情的罕见，把医生们都吓倒了，但是他们很快冷静下来，给病人做全身检查。