What are the modes of acquiring Philippine citizenship?

There are two (2) generally recognized modes of acquiring Philippine citizenship, namely:

1) by birth; and

1) Jus soli (right of soil) which is the legal principle that a person's nationality at birth is determined by the place of birth (ie, the territory of a given state).

2) Jus sanguinis (right of blood) which is the legal principle that, at birth, an individual acquires the nationality of his/her natural parent/s. The Philippines adheres to this principle.

2) by naturalization which is the judicial act of adopting a foreigner and clothing him with the privileges of a native-born citizen. It implies the renunciation of a former nationality and the fact of entrance into a similar relation towards a new body politic.

Further.

The above is nation specific but the rules stated generally refer to most other countries.

You would need to check the specific legislation of the country in question.