cannot avoid doing; have no choice but to do; must do
Fixed expression meaning that one is compelled to do something, often due to external circumstances. Attaches to the imperfective form (未然形) of a verb. Similar to せざるを得ない, but used with する verbs (e.g., 勉強せざるを得ない → 勉強やらざるを得ない).
See also: せざるを得ない
The deadline is near, so I have no choice but to do it right away.
No one helped me, so I had no choice but to do it alone.