Can anybody help me to pronounce this sentences of Irish.

The sentences:

An ataireachd ard,
Cluinn fuaim na h-ataireachd ard,
Tha torunn a' chuain,
Mar a chualas leums' e nam phaisd,
Gun mhuthadh, gun truas,
A' sluaisreadh ganneimh na tragh'd,
An ataireachd bhuan


And why put the apostrophe? such as:
a' chuain,
leums',
A' sluaisreadh,
tragh'd