(2)如果不定式充當的主語較長而謂語較短時,常用形式主語“it”放在謂語之前,而把真正的不定式主語放在句子后面。如:It is my duty to take care of these kids.
(3)有時,不定式的前面可以有一個連接詞、連接代詞或連接副詞(包括whether, what, which, whom, where, when, how)。如:
Where/When/How/Who to prepare the dinner is not decided yet.
2、動名詞作主語
動名詞相當于一個名詞,可以充當句子主語。如:Being a man has always been dangerous.
還有一種情況,當動名詞有自己的邏輯主語時,其前加上一個名詞或代詞的所有格,構成動名詞的復合結構(這時,名詞或代詞的所有格做動名詞的邏輯主語)。動名詞的復合結構也可以在句中作主語。如:
Everyone’s being the same in survival and number of offspring means that natural selection has lost 80% of its power in upper-middle-class India compared to the tribes.