一般時 過去將來 過去 現(xiàn)在 將來
should 動原 動原ed 動原 shall 動原
進行時 過去將來 過去 現(xiàn)在 將來
should be was am shall be
were is
are
完成時 過去將來 過去 現(xiàn)在 將來
should have had has shall have
have
完成進行時 過去將來 過去 現(xiàn)在 將來
should have been had been has been shall have been
have been