Without outside help.
Not requiring anything further; merely.
By oneself; apart from, or exclusive of, others; solo.
Used to emphasize the size or extent of something by selecting a subset.
Not permitting anything further; exclusively.
By oneself, solitary.
Lacking peers who share one's beliefs, experiences, practices, etc.
without outside assistance
Alone; without assistance or help from others.
Alone, without another's immediate company
Used other than figuratively or idiomatically: see by, oneself.