Bilet gişesi önünde neredeyse herkes uzun kuyrukta bekler.

Neredeyse translates as “almost” or “nearly.” It’s an adverb that modifies the subject (herkes) to show that the statement applies to the vast majority, but not literally 100%. You can place it before or after the subject:

• Neredeyse herkes uzun kuyrukta bekler.
• Herkes neredeyse uzun kuyrukta bekler.
  Both are grammatically correct, though the first (adverb + subject) is more common for emphasis on “almost everyone.”

Turkish uses the simple present (-r suffix) for general truths or habits. Here it states what people typically do at the ticket booth:

• bekler = “(they) wait” (habitual/general)
  If you want to describe right now, in progress, you’d use the present progressive:
• bekliyor = “(they) are waiting” (right now).

In Turkish, herkes (“everyone”) is grammatically singular, so it takes a singular verb (no -ler). You always say:

• Herkes geliyor. (Everyone is coming.)
  Not herkes geliyorl ar.

Bilet gişesi literally means ticket booth or ticket office. It’s a noun-noun compound:

• bilet (ticket) + gişe (booth/office) = the booth where you buy tickets.
  In many Turkish noun compounds, the first noun stays bare (no genitive suffix). Adding -in would over-mark possession: biletin gişesi = “the booth of the ticket” which sounds odd in Turkish.

Morphological breakdown of önünde (“in front of it”/“in front of [something]”):

• ön = front
• -ü = 3rd person singular possessive (“its/one’s front”)
• -nde = locative case (“at/in/on”), made of buffer n
  • -de

Put together: ön + ü + nde → önünde = “in front of [that thing].”

kuyrukta comes from kuyruk (queue/line) + locative -ta (or -te after front vowels). Locative here means “in the queue/in line,” indicating where the waiting happens. You could say:

• uzun kuyrukta beklemek = “to wait in a long queue.”

Turkish has no definite or indefinite article like a/the. You can optionally add bir for indefiniteness or emphasis:

• uzun kuyrukta = “(in) a/the long queue” (neutral)
• uzun bir kuyrukta = “in a long queue” (stresses “a certain long queue”).
  In everyday speech, omission of bir is more common when the adjective-noun pairing is clear.

Turkish is fairly flexible, but the unmarked order is Subject–Object–Verb. Adverbials (like location phrases) can go at the beginning or before/after the object for emphasis or style:

• Bilet gişesi önünde neredeyse herkes uzun kuyrukta bekler. (Topic/emphasis on location)
• Neredeyse herkes uzun kuyrukta bilet gişesi önünde bekler. (More neutral)
• Neredeyse herkes uzun kuyrukta bekler bilet gişesi önünde. (Less common, more poetic)
  Choose placement based on what you want to highlight.