How can I identify a strong base?
Either by looking at the formula or the Kb.
The easiest way to establish the basicity (basic nature or strength of the base) is to look at the Kb. The higher the Kb, the stronger the base.
Generally, looking at the formula can also give some indication as to the relative strength of a base. If it is a hydroxide of group 1 or 2 (with the exception of beryllium), or oxides (to the extent they are soluble) of the same groups, it is a strong base.
Base strength is determined by the extent to which a base will dissociate, but also the extent to which it will remove a proton from an acid.