没有留下任何痕迹...

n.避孕药，避孕用具( contraceptive的名词复数 )...

Oral contraceptives are readily available.口服避孕药容易得到.Some barrier contraceptives also help to protect against sexually transmitted infections.有些屏障避孕还有助于预防性传播疾病.Continuous Oral Contraceptives: Are Bleeding Patterns Depende...

adj.不能回头的，不能再找到的...

contraceptives的音标：contraceptives的英式发音音标为：[kɒntrə'septɪvz]contraceptives的美式发音音标为：[kɒntrə'septɪvz]...

v.折回( retrace的过去式和过去分词 )，回忆，回顾，追溯...

n.追踪者，描图者，（铁笔等）绘图工具...

trace的现在完成时为：traced...

小脑外的...

contraceptive的复数形式为：contraceptives...

免疫避孕...

Celastraceae的音标：...

He often retraces the happy time during his young age.他经常回忆起年轻时代的幸福时光....

The law allows doctors to prescribe contraception to the under 16s.法律允许医生给16岁以下未成年人开避孕药。She is known to have liberal views on divorce and contraception.众所周知，她在离婚与避孕方面思想很开明。to give advice about contraception就避孕方法提供咨询...

Oral contraceptives are readily available.口服避孕药容易得到....oral contraceptives...口服避孕药Continuous Oral Contraceptives: Are Bleeding Patterns Dependent on the Hormones Given?连续口服避孕药: 出血模式是否依赖于服用的激素?Some barrier contraceptives ...

The tracer is distributed in a nearly normal fashion.示踪剂的分布接近正态分布的样式.Tracer techniques give information about structure and reactions in solid state physics.示踪法技术在固态物理学方面给出有关结构和反应的信息.This solute will be referred to as a ...

adj.（位于或发生于）细胞外的...

n.赛舟，竞渡...

宏观查找，宏观探索，宏追踪...

immunocontraception的音标：immunocontraception的英式发音音标为：[ɪmjʊnəʊkɒntrə'sepʃn]immunocontraception的美式发音音标为：[ɪmjʊnoʊkɒntrə'sepʃn]...

Most telephone calls are traceable.大多数电话都可查出是从哪里打来的。Britain's inflation is probably traceable in part to the Chancellor's failure to get the exchange rate right.英国的通货膨胀有一部分大概要归因于财政大臣未能将汇率控制在合理水平。Most telephone ...

footrace的音标：footrace的英式发音音标为：['fʊtreɪs]footrace的美式发音音标为：['fʊtˌreɪs]...

adj.细胞内的...

Wash them in cold water to remove all traces of sand.用冷水冲洗它们以清除所有的沙子。Meat which has been cooked thoroughly shows no traces of pinkness.彻底煮熟的肉不会带有血色。The local church has traces of fifteenth-century frescoes.当地教堂仍留有15世纪壁画的...

retrace的音标：retrace的英式发音音标为：[rɪ'treɪs]retrace的美式发音音标为：[ri'tres]...

intracell的音标：intracell的英式发音音标为：[ɪntrə'sel]intracell的美式发音音标为：[ɪntrə'sel]...

intracellular的音标：intracellular的英式发音音标为：[ˌɪntrə'seljʊlə]intracellular的美式发音音标为：[ˌɪntrə'seljələ]...

v.描绘( trace的过去式和过去分词 )，追溯，发现，跟踪...

vt.折回，折返，回忆，回想，追溯，探源，重描...

We continuously inject a tracer into a point in a steadily moving fluid.我们连续地将一种示踪物注入某稳定运动流体中之一点.When ~ ( 238 ) Pu is used as a tracer, its recovery is 77±10 %, with activity being 0.29 dpm.当使用~ ( 238 ) Pu作示踪剂, 强度在0.29dp...