weight和weights分别是weigh和high的名词。weight是动词，weights是名词。50kg重，用weight，但要知道50kg重前，需要weigh一下。
weigh：
1、Weigh 作动词的基本意思是“称…的重量”。
Cao Chong thought of a way to weigh the elephant．曹冲想出了一个称大象的办法。
Can you weigh this letter for me please? 能帮我称一下这封信吗
2、 Weights引申可以表示“仔细考虑某事物的相对价值或重要性等”，也就是“权衡”“斟酌”，为及物动词。
He weighed the ideas in his mind. 他在脑中权衡着这些想法。
He has to weigh his words when he talks to her. 他对她说话都得小心翼翼。
3、 Weigh引申还可表示感伤、恐惧或忧虑的事给思想或精神带来压力，使人感到烦扰或悲痛。
固定短语weigh on表示“重压于；使苦恼”。
The wealth did not weigh on me. 这笔财富不再使我感到沉重。
weight和weights有什么区别
weight意思是重量；分量；重；重物。weights是weight的复数形式。