Take two: He's good at singing
An dàrna turas: Tha e math air seinn
Let's have a look at this conversation again.

An cuala tu?
Did you hear?

An cuala mi dè?
Did I hear what?

Tha Iain a' dol chun a' Mhòid am-bliadhna. Agus tha Fionnlagh a' toirt lioft dha.
John is going to the Mod this year. And Finlay is giving him a lift.

Math fhèin! Saoil am biodh e comasach dhuinn lioft fhaighinn còmhla riutha?
Excellent! I wonder if it will be possible for us to get a lift with them?

A bheil Iain math air seinn?
Is John good at singing?

Tha gu dearbh. Tha e math air seinn, ach tha e nas fheàrr air a' ghiotàr. Bha e comasach air bonn no dhà a chosnadh nuair a bha e òg.
He is indeed. He's good at singing, but he's better on the guitar. He was able to win a medal or two when he was young(er).

An robh thusa math air seinn nuair a bha thu òg?
Were you good at singing when you were young?

Cha robh mi dona. Bha mi aig a' Mhòd uair no dhà. Agus dè mu do dheidhinn-sa?
I wasn't bad. I was at the Mod once or twice. And what about you?

Tha e comasach dhomh òran no dhà a ghabhail, agus thèid agam air ceòl a leughadh, ach chan eil e comasach dhomh seinn air an àrd-ùrlar. Bidh mi gun chomas idir!
I am able to sing a song or two, and I can (manage) to read music, but i can't sing on (the) stage. I just won't (I am without ability at all).

Carson?
Why?

Tha eagal orm ron luchd-èisteachd, ron àrd-ùrlar ... ro rudeigin! Ach thèid agam a bhith san talla ag èisteachd ri Iain!
I am afraid of the audience, of the stage ... of something! But I can manage to be in the hall listening to John!

Agus bidh e comasach dhomhsa a dhol ann cuideachd. 'S urrainn dhomh làithean-saora a ghabhail aig an àm sin.
And I will be able to come as well. I can take holidays at that time.

Nach eil e comasach dhut fònadh gu Fionnlagh an-dràsta?
Can't you (aren't you able to) phone Finlay just now?

Tha e comasach dhomh. Fònaidh mi thuige an-dràsta fhèin.
I can (am able to). I'll phone him right now.

Abair splaoid a bhios againn!
What a trip we'll have!