A particle used for marking the following verb as an infinitive.
As above, with the verb implied.
Used to indicate an obligation on the part of, or a directive given to, the subject.
In order to.

In the direction of; towards.
Indicating destination or final position: In the direction of, so as to arrive at or reach.
Used to indicate the target or recipient of an action.
So as to contact, press against, impact, etc.
So as to become or reach: indicating a terminal state resulting from an action.
So as to bring about or elicit (an effect or outcome).
Used after an adjective to indicate its application.
Indicating a degree or level reached.
Used to describe what something consists of or contains.
Denotes the end of a range.
(obsolete) As a.
Used to indicate a ratio or comparison; compared to, as against.
Used to indicate that the preceding term is to be raised to the power of the following value; indicates exponentiation.
Preceding (the stated hour).
(informal) Preceding (the stated hour).
According to.
(Canada, Newfoundland, Wales) At.
Used more-or-less idiomatically with various verbs: keep to the left, agree to the proposal, attend to the matter, etc. See the individual entries.