In summary: adverbs tell manner (how), time (when), place (where), degree (how much), and sometimes cause (why).
Adverbs of manner: "politely, carefully, not, equally, tenderly".
Adverbs of time: "now, then soon, later, early, often".
Adverbs of place: "here, there, near, forward, far."
Adverbs of degree: "very, so, much, too, extremely, rather."
Adverbs of cause: "why, therefore, hence".
2. In a secret or concealed manner; invisibly: "She was latently infected, but the doctor was able to find a medical cure."