portative force

• 吸力

portative force的用法和样例：

例句

1. An apple falls by the force of gravitation.
   地心吸力使苹果落地。
2. A vacuum sucking system is equipped and the sucking force can be adjusted to feed the curved paperboard in.
   采用真空辅助吸纸自动踢刀送纸系统，分级调整吸力，使弯曲纸板自动顺利送入。