"Yáʼátʼééh abiní shimá."
Translation:Good morning mother.
The accents indicate the higher tone. No accent, lower tone.
Apostrophes are glottal stops (like the hitch in the voice between "uh" and "oh" in English's "uh-oh").
The vowels are pronounced similar to the way they would be in Spanish. A single vowel is a short vowel. A double vowel is a long vowel (literally take a little longer saying it).
A hook under a vowel means nasalize it.
The consonants are pretty close to what you'd expect, except for a few combinations (none of which are in this exercise). Slashed L is a voiceless L. "gh" is almost like a "w" sound, except it's made in the back of the mouth, not the front.
"Sh" is like the "sh" in "she," "zh" like the "z" in "azure," and "ch" like the "ch" in "cheese." Otherwise, h usually indicates aspiration (breathe a little at the end of yáʼátʼééh). X is also used for aspiration (so sx would be an aspirated s).
Hard consonants that we usually aspirate in English aren't aspirated in Navajo unless indicated (by an H or X).
I hope that helps a little! Once you learn all the pronunciation rules, it makes it a lot easier. Words are pronounced exactly as written.