strong （强壮的），反义词weak（虚弱的，弱小的）。

strong造句：He is a strong man。

他是一个强壮的男人。

weak造句：And even stumbling speech may strengthen a weak tongue.即使是磕绊的话语也会强壮无力的舌头。

例句：

1.I was too weak to move or think or speak

我太虚弱了，无法动弹，无法思考，也无法说话。

《柯林斯高阶英汉双解学习词典》

2.Until the beating, Cantanco's eyesight had been weak, but adequate

挨打前坎坦科的视力就一直很弱，不过也还勉强看得见。

《柯林斯高阶英汉双解学习词典》

3.He was a nice doctor, but a weak man who wasn't going to stick his neck out

他是位为人和蔼的医生，但胆小怕事，不敢冒什么风险。

《柯林斯高阶英汉双解学习词典》

4.His weak voice was almost inaudible

他的声音微弱，几乎听不见。

《柯林斯高阶英汉双解学习词典》

5.The owner said the bird may have escaped through a weak spot in the aviary

鸟的主人说这只鸟可能是从鸟舍一处不结实的地方逃走的。