Television can not dwell upon a subject or explore it deeply, an activity for which the static, lineal form of typography is well suited.
这里activity 是同位语?作句子的同位语?
an activity是对 dwell upon a subject or explore it deeply的解释和说明。可以认为是不带to的不定式的同位语 (情态动词后接不带to的不定式)。因为在意义上二者有同位关系。
To dwell upon a subject or explore it deeply is an activety for which...。
再看一个名词作句子的同位语结构:
One plus one is two, a fact that everyone knows.
a fact为前面句子的同位语。
That one plus one is two is a fact that everyone knows.
如果觉得我的回答对您有用,请随意打赏。你的支持将鼓励我继续创作!