sy / sydd
Who, Which: Sy and Sydd
Use sy to say who is or which is: y dyn sy'n byw drws nesa (the man who lives next door).
How It Works
Joining two ideas.
- Dyma'r ferch. Mae hi'n byw drws nesa. → Dyma'r ferch sy'n byw drws nesa. (This is the girl who lives next door.)
Sy works with every kind of description.
- + yn + verb-noun: y dyn sy'n canu (the man who is singing)
- + wedi: y tîm sy wedi ennill (the team that has won)
- + a place: y llyfrau sydd ar y bwrdd (the books that are on the table)
- + eisiau: y bobl sy eisiau helpu (the people who want to help)
Sy and sydd. Sydd is the full form, used in writing and careful speech. Sy is the everyday spoken form, and sydd yn becomes sy'n.
Negatives. Speech simply adds ddim: y plant sy ddim yn dod (the children who aren't coming). Formal Welsh uses nad yw.
Only for the subject, only in the present. Sy means who or which is or are. For the past and future, use oedd and fydd. When the noun is the object (the film that I saw), use relative a: y ffilm a welais i.
Sy is also used in questions like Pwy sy'n dod? and for emphasis: Fi sy'n talu (It's me who's paying).
Examples (6)
- Dw i'n nabod dyn sy'n siarad Cymraeg.
I know a man who speaks Welsh.
- Mae'r llyfrau sydd ar y bwrdd yn newydd.
The books that are on the table are new.
Sy stays the same with a plural noun.
- Mae angen rhywun sy'n gallu gyrru.
We need someone who can drive.
- Mae'r trên sy'n mynd i Gaerdydd yn hwyr.
The train that goes to Cardiff is late.
- Mae'r plant sy ddim yn dod yn sâl.
The children who aren't coming are ill.
The spoken negative is sy ddim.
- Llongyfarchiadau i'r tîm sy wedi ennill!
Congratulations to the team that has won!
Common Mistakes
Using mae inside a who or which clause.
Dw i'n nabod dyn mae'n siarad Cymraeg.Dw i'n nabod dyn sy'n siarad Cymraeg.When the noun does the action in the second part, use sy instead of mae.
How It Connects
Learn This First
Sy is the relative present of bod.
Related Patterns
- Pwy sy...? / Beth sy...?Who Is? What Is? Pwy Sy and Beth Sy
Sy in questions: Pwy sy'n dod?
Level 3 - Emphasis by Fronting
Sy after a fronted subject: Fi sy'n talu.
Level 4 - Relative oedd / fyddRelatives in Past and Future: Oedd and Fydd
The past and future versions.
Level 4 - Negative Relative na / nadNegative Relatives: Na and Nad
The formal negative.
Level 4 - Relative a + Soft MutationRelative a: Y Dyn a Welais I
When the noun is the object instead.
Level 4 - Present of bodPresent Tense of Bod
The forms sy replaces.
Level 1
Learn Next
Patterns that build on this one.
Words in This Pattern
Practice sy / sydd in Bubblegum
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