My understanding is that 现在分词可以做主语. For example, Seeing is believing.
However, the phrase "Having studies" cannot be used as a subject, for the phrase is used as an adverb to talk about time or condiciton.
For example, Having studied this for two years he is still not confident on the mastery of the essense of it.
However, the phrase "Having studies" cannot be used as a subject, for the phrase is used as an adverb to talk about time or condiciton.
For example, Having studied this for two years he is still not confident on the mastery of the essense of it.