到目前为止，总统一职在很大程度上只是礼仪性的。Up to now the post of president has been largely ceremonial.她不适合这种场合，对社交礼仪所知甚少。She didn't fit in and she had few social graces.年轻女士的礼仪课lessons for young ladies in deportment and etiquette...
染色质DNA在细胞分裂之前必须复制.The DNA of chromatin must replicate before cell division.异染色质大部分是由短而重复的多核苷酸序列所组成的.Heterochromatin has shown to be composed largely of short repeated polynucleotide sequences.那些表现 “ 正常的 ” 浓缩格式的部分叫做常染色质.T...
这种植物现在有绝种的危险.The plant is now in danger of extinction.温斯顿觉得, 查林顿先生也算个绝种的动物呢.Mr Charrington, thought Winston, was another extinct animal.某些绝种的头足类动物具有特殊的旋卷形态.Certain extinct cephalopods have an unusual coiling shape....