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- primary sex characteristics 第一性征
- primary sex characteristic 主性征
- As a boy goes through adolescence, his secondary sex characteristics develop. 作为一个青春期男孩，这是他的第二性征在发展。
- Serious Faults--Lack of proportion, undersized, oversized, reversal of sex characteristics (bitchy dogs, doggy bitches). 主要缺陷：比例不当，身高过高或过低，性别颠倒（象雌性的公狗或象雄性的母狗）。
- Any of several steroid hormones produced chiefly by the ovaries and responsible for promoting estrus and the development and maintenance of female secondary sex characteristics. 雌激素一种主要由卵巢分泌的类固醇激素，用来刺激性交，形成和保持女性的第二性特征
- Results A total of 509 participants met inclusion criteria and signed informed consent. 33.4 % participants shared needles last 3 months. 20.4% drug users had an IDU primary sex partner. 近1个月与固定性伴和非固定性伴从未使用安全套的比例分别为85.;8%25和69
- Human chorionic gonadotrophin (HCG), 2000U, i. m. twice a week, and oral testosterone undecamoate were administered.The sex characteristics were more obvious and the gonad developed after therapy. 给予人绒毛膜促性腺激素2000U每周2次肌肉注射，口服十一酸睾丸酮治疗，病人性征较前明显且性腺发育。
- One having the reproductive organs and many of the secondary sex characteristics of both sexes. 两性体具有生殖器官和第二性征的许多特点的个体
- Because the male and female amphoteric physiology,the psychological difference as well as the social factor influence,causes them to present the different sex characteristic in the Chinese study. 由于男女两性生理、心理的差异以及社会因素的影响,使得他们在语文学习中呈现出不同的性别特点。
- The disease is still in its primary stage. 这疾病仍然在初发阶段。
- The little boy left primary school at eleven. 这个小男孩十一岁时小学毕业。
- Sure. We are friends since primary school. 当然，我们从小学就是朋友了。
- I started primary school when I was 5 years old. 我五岁时开始读小学。
- A primary cause of Tom's failure is his laziness. 懒惰是汤姆失败的主要原因之一。
- Primary school teachers use a lot of visual aids. 小学教师使用大量的视觉教具。
- Love and hatred are primary emotions. 爱和恨是基本的情感。
- (especially of domestic fowl) breeding to reveal differential sex characteristics at hatching. （尤其指家禽的）根据孵出时显现的不同性别特征饲养。
- The Democratic primary was held this month. 民主党候选人初选於本月举行。
- Primary education comes under the umbrella of local government. 小学教育受地方政府的保护。
- (especially of domestic fowl) breeding to reveal differential sex characteristics at hatching （尤其指家禽的）根据孵出时显现的不同性别特征饲养
