He can swim. So can I.
I didn’t go to class. Neither did I.
結構：
so/neither+be+ 主語
so/neither+助動詞+ 主語
so/neither+情態動詞+ 主語
一般現在時, do, does/am, is, are
現在進行時, am, is, are
一般過去時, did
現在完成時, have, has
一般將來時, will, shall,
過去進行時，was, were
過去完成時，had
過去將來時, would
