口软的英文：
flaccidity of mouth in infants

flaccidity是什么意思：
n. 软弱,没气力

The penis is usually in a flaccid state.
阴茎常处于萎软状态。

Paralysis (palsy)：Loss or impairment of voluntary use of one or more muscles. It may be flaccid (with loss of muscle tone) or spastic (stiff).
瘫痪(亦称麻痹):一块或多块随意肌肌力丧失或减弱的症状。表现为肌肉无力或僵硬。

He's neither a progressive who posed as a moderate, nor a flaccid centrist who pretended to have transformational ambitions.
他既非假装温和派的改革主义者，也非假装具有改革雄心的软弱无力的中间派。

mouth是什么意思：
n. 嘴；入口；需要供养的人；讲话方式
v. 不出声地说，言不由衷地说

Live from hand to mouth
勉强糊口

To live from hand to mouth
得过且过

A close mouth catches no flies
病从口入

infants是什么意思：
n.
1.婴儿，幼儿
2.【律】未成年人（18岁以下者）

Association of Infant Formula Manufacturers
婴儿配方奶制造商协会

The order will be for the welfare of the infant.
该命令将保障未成年人的福利。

It would be wrong to sexually fondle an infant even if the infant was not physically harmed or traumatized.
即便没有对未成年人造成肉体或精神上的伤害，对未成年人进行性爱抚依旧是错误的。