"He speaks English easily and clearly."

Translation: Labhraíonn sé Béarla go héasca agus go soiléir.

[MaryLea11]

Is her pronunciation of 'go héasca' to be trusted?

[19O492554]

There is usually a diphthong in éasca - you can hear both the é and the a before the s, but in ordinary speech that nuance is often missing.

[freymuth]

The recording here puts a little more emphasis on the "a", but it seems like a reasonable pronunciation compared to éasca

[DeborahAnn828887]

So is "go" always used for the english equivalent of "ly" adverbs like clearly and easily?

[Knocksedan]

No. While the general rule is that you can use an adjective as an adverb by adding go, there are exceptions.

Sometimes you just wouldn't use an adverb in Irish - for example, a quick search for sentences containing "easily" in the NEID throws up examples like:
"you're easily satisfied" - is furasta tú a shásamh (it is easy to satisfy you)
"easily digested food" - bia atá éasca a dhíleá (food that is easy to digest)
"that's easily understood" - tá sé sin sothuigthe (that's understandable)
"I'm not easily shocked" - ní furasta náire a chur orm (it's not easy to embarrass me)
(there are lots of examples with go héasca and go furasta too).

You also don't use go if the adverb is qualifying an adjective:
"it's fairly simple" - tá sé réasúnta simplí
"it's extremely big" - tá sé millteanach mór
"they didn't act quickly enough" - níor ghníomhaigh siad gasta go leor (go is part of go leor, not go gasta).

[DeborahAnn828887]

I wish I could sit in a room with you and work this all out. Thank you again for clarifying things for me.