ascertain-v; 2 Senses

Sense Number 1: Find out or determine, perhaps after a calculation or investigation.

Commentary: Syntax Is: NP1[agent] ASCERTAIN [proposition]

We use multiplication to ascertain the product of two numbers.
I want to ascertain whether she speaks French.
Chuck ascertained the pipe's pressure before opening the valve.

VerbNet: discover-84
FrameNet: Coming_to_believe
PropBank: ascertain.01
WordNet 3.0 Sense Numbers: 1, 3, 4

Sense Number 2: Make sure of.

NOTE: Usually phrased as some sort of imperative.

Ascertain that the curtains are closed.
We must ascertain the good quality of our products.
Ascertain that dinner has been prepared.

VerbNet: ensure-99,promise-37.13
FrameNet: NM
PropBank: NM
WordNet 3.0 Sense Numbers: 2