Yes, it means in a horizontal, side-to-side or "lengthwise" orientation, and can be the opposite of "vertically" (up-and-down, top-to-bottom).
Yes the word horizontally is an adverb.
For example: I drew the line horizontally.
The adverb form of the adjective 'tragic' is tragically.
pointy
No, neither word is being used as an adverb. Position is a noun and upright is an adjective describing the position desired.
Jonah is a proper noun.
Sunny is an adjective. We say: A sunny day. A sunny disposition. The sunny side of the street. The adverb 'sunnily' has rare but specific uses.
Horizontally
horizontally
Cells that run horizontally
Stems which grow horizontally are called stolons. Stems which grow horizontally are called stolons.
It was such a beautiful day, I decided to spend it horizontally on the beach
When air is moving horizontally, that is known as wind.
Horizontally
both vertically and horizontally
vertically and horizontally. Vertically, they get taller as new growth sprouts from the top every year. Horizontally, they get thicker and branches get longer.
Horizontally
An image shot horizontally is called a landscape photograph.
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