He is doubling the parts of a preacher and a teacher.

他扮演牧师和教师两个角色。

He is doubling the part of a teacher and a missioner.

他在一出戏里扮演教师和传教士两个角色。

In plants this is sometimes overcome by the doubling of the chromosome number, giving an allopolyploid.

在植物中，这种不育现象有时可因为染色数目而抵消，产生同源多。

In the play, Mary is playing the part of the dancer and doubling as the mother.

玛莉在剧中扮演那名舞蹈演员，兼演剧中的。

In contrast to homoploid hybrid species,polyploid species are easily diagnosed because of chromosome number changes associated with genome doubling.

同杂合物种相比，因为基因组相关的染色数目的变化,多杂合物种很容易判断。

Fireresistant Hall device and SmCo rotor is used to design position and speed sensor, and the corresponding doubling circuit and decoding circuit is designed.

采用耐高温的锁定型霍尔元件和钐钴永磁转子分别构成位置速度传感器，设计相应的速度信号频电路位置信号译码电路。