multiply

/ˈmʌl.tə.plaɪ/

to reproduce in large numbers; to make sth do this （使）繁殖，增殖
Rabbits multiply rapidly.
兔子繁殖迅速。

~ sth
It is possible to multiply these bacteria in the laboratory.
在实验室里繁殖这些细菌是可以做到的。