Though it may be possible to measure the value of material good in terms of money,it is extremely difficult to estimate
问题描述：
Though it may be possible to measure the value of material good in terms of money,it is extremely difficult to estimate the true value of the services which people perform for us.这里的2个不定式是什么语 which是状从吗
答
to measure the value of material good in terms of money
to estimate the true value of the services 都作主语
which 引导定语从句