这句话对吗：Crude methanol from coal and natural gas is both favorable feedstock for the process. 受句意影响，是不是应该改成Crude methanol(s) from coal and natural gas are both favorable feedstock for the process.虽然methanol应该是没法加s的，不可数。

我知道这几句话是对的：Crude methanol from both coal and natural gas is favorable feedstock for the process.

                              It is both an art and a discipline.

                              It is both expensive and dangerous.