What you are getting from a statement might not be necessarily true. Let us burst some of the common misconceptions

Oxygen is necessary for burning, so it is highly flammable 
If we have materials for burning, then adding oxygen feeds the flame. It is, therefore, dangerous to keep oxygen near any kind of fire. 
Does this mean oxygen itself is flammable or burns? 
To find out, you can take a jar containing oxygen gas. Now if you ignite it, you will not find anything happening - the match stick will burn out after sometime but will not see a fire.

$$F_2O$$ is called difluorine oxide 
$$Cl_2O$$ is dichlorine oxide and $$I_2O$$ is diiodine oxide. 
What would you call $$F_2O$$? Difluorine oxide? 
Before you answer, remember that while naming a compound, the electropositive element is written first followed by the electronegative element. 
In $$Cl_2O$$, Cl is more electropositive and is written first followed by electronegative element (O). That's why it is called dichlorine oxide. 
But when it comes to $$F_2O$$, F is more electronegative than O. So, the compound is called oxygen difluoride and NOT difluorine oxide.

$$O=P(OH)_3$$ is a base and $$PH_3$$ is an acid 
According to the conventional theory of acids and bases, $$O=P(OH)_3$$ with 3 OH units is more likely a base while $$PH_3$$ with H units an acid. 
Instead, the reverse is true. 
This happens because the O-H bonds in $$H_3PO_3$$ are ionizable while the P-H bonds in $$PH_3$$ are non-ionisable.

<div>This makes $$H_3PO_3$$ a tribasic acid.</div>
<div>Coming to $$PH_3$$, it has a lone pair of electrons available for donation. Therefore, $$PH_3$$ acts as a Lewis base.</div>

The P-Block Elements