嚟嘅 (lei4 ge3)

The particle 嚟 (lei4) here is grammaticalized, meaning it doesn't mean 'to come' but acts as a marker for identifying what something is. Note that 嚟 is also frequently pronounced and romanized as lai4 (e.g., lai4 ge3 / lai4 gaa3). Both lei4 and lai4 are completely interchangeable in this context.

Key Features:

• The Full Formula: The underlying structure is [Subject] + (係) + [Noun] + 嚟嘅 (e.g., 佢係醫生嚟嘅 - He is a doctor).
• Optional 係 (hai6): Unlike English, you don't always need 'is'. The 係 can be dropped, making '佢醫生嚟嘅' perfectly natural. In fact, dropping '係' is standard, everyday spoken Cantonese at any speed, because '嚟' has grammaticalized to carry copular weight in this specific structure.
• Contrast with simple 係: Why use 嚟嘅 instead of just 係? This pattern is fundamentally explanatory. You use it to clarify what something is when the listener doesn't know, is asking about it, or might be mistaken. You wouldn't use it for obvious facts (e.g., a man shouldn't say '我係男人嚟嘅' to someone who can clearly see he is a man).
• Nouns and Nominalized Phrases: This pattern is primarily used with nouns or noun phrases. However, you can also use verb-object phrases that act conceptually as nouns (e.g., 呃人 aak1 jan4 'scamming', 講笑 gong2 siu3 'joking'). You cannot use it with adjectives.
• Negation: To say something is NOT something, use 唔係 (m4 hai6) before the noun. Keeping 嚟嘅/㗎 at the end is optional, but doing so adds an explanatory or corrective nuance (e.g., 呢個唔係我部機嚟㗎).
• Yes/No Questions: The most standard way to ask a Yes/No question with this pattern is using the A-not-A structure 係咪 (hai6 mai6) with the particle 㗎 (gaa3) (e.g., 佢係咪本地人嚟㗎？ - Is he a local?). Alternatively, you can use the questioning particle 呀 (aa4), resulting in the fusion 㗎 (gaa4) (e.g., 你醫生嚟㗎？ nei5 ji1 sang1 lei4 gaa4? - Are you a doctor?).
• 嚟㗎 (lei4 gaa3) and Etymology: The particle 㗎 (gaa3) is a phonetic fusion of 嘅 (ge3) and the softening particle 呀 (aa3). It is used in WH-questions like '乜嘢嚟㗎？' (What is this?) and '邊個嚟㗎？' (Who is this?). Note that dropping 係 is the overwhelming norm in daily speech for WH-questions (e.g., '呢個咩嚟㗎？' is far more common than '呢個係咩嚟㗎？'). In declarative statements, there is a key difference: [Noun] + 嚟嘅 is a firm, objective assertion of a fact, whereas [Noun] + 嚟㗎 softens the assertion, acting as a friendlier explanation or gentle reminder. Importantly, [Noun] + 嚟嘅 is the standard, direct answer to these questions (e.g., Q: 乜嘢嚟㗎？ mat1 je5 lei4 gaa3? - What is it? / A: 蘋果嚟嘅。 ping4 gwo2 lei4 ge3. - It's an apple.).
• 嚟嘅啫 (lei4 ge3 ze1): A common variation meaning 'it's just...'. Use this to downplay something (e.g., '講笑嚟嘅啫' - It's just a joke).
• Literal Overlap: Be aware that when used with locations, 嚟 retains its literal meaning of 'to come' (e.g., '我香港嚟嘅' ngo5 hoeng1 gong2 lei4 ge3 means 'I come from Hong Kong', not 'I am Hong Kong').
• Informal Written Variants: In casual texting or internet forums, native speakers often substitute 嚟 with 黎 (lai4) or 來 (loi4/lei4), 㗎 is sometimes typed as 架, and 嘅 is commonly substituted with 既 (e.g., 黎既).