if they knew how difficult it was to drill through the hard rock,they would lose heart请帮我分析下这段话的语法结构.

supply +gas/water etc. 用在utility上面的居多
offer + drink/paper
provide + services
offer: 常用词，意为" 提出，提供，呈现"，表示向别人提供可接受也可拒绝的某物，如帮助，服务或物品，这可能是对方要求也可能是自己主动提出的。
offer to help sb. offer sb. sth./ offer sth. to sb.
provide: "供给，提供，装备，准备"，强调有预见，并通过储存或准备的方式为某事做准备，以在需要时提供所需物品。常用词组：provide sb. with sth./ provide sth. for sb. 提供生活费，养活，为……做准备。例如：
supply: "供给，补充，弥补"，着重表示替换或不足所需之物以及弥补缺陷，满足要求的意思，还可作名词，意为“供给（量），物资，存货”。

if they knew how difficult it was to drill through the hard rock条件状语从句
how difficult it was to drill through the hard rock宾语从句
it was to drill through the hard rock中的it是形式主语
it was to drill through the hard rock中的to drill through the hard rock是不定式做真正的主语,
they would lose heart是整个句子的主语
要是还有不懂的再问我