multiply

细菌在适宜条件下会迅速繁殖。

Bacteria can ___multiply rapidly under favorable conditions.

如果你把3乘以5，会得到15。

If you ___multiply 3 by 5, you'll get 15.

如果你把5乘以4，结果是20。

If you ___multiply 5 by 4, the result is 20.