...tons of amber were used...

问题描述:

...tons of amber were used...
...thousand tons of amber were used to make it.
请问为什么这里要用were,而不用was呢?

thousand tons of是上千吨的 是复数 虽然amber不可数 但这里的were是修饰tons的 所以用were
比如 paper不可数 但是说pieces of paper就可以数了