The most common shielding gases used for these main arc welding processes include argon (Ar), helium (He), carbon dioxide (CO2) and oxygen (O2). While Ar, He and CO2 may be used by themselves (i.e. 100%) for certain applications, in other cases the four gases are mixed together in different combinations to form shielding gas blends.
Cluster reduction in speech is when a consonant cluster, that is two or three consonants occurring in sequence in a word (like ândâ in friend), is reduced by a child into a single consonant through omission.
Since we don't have the NG initial consonant cluster in English, it can be challenging. But this is how I show people how to pronounce it: 1. Say singing but instead of separating the syllables as sing-ging, try to carry the N from the first syllable over to the second (sin-nging). If you know how to pronounce Songhai or Songhay correctly, it's the same NG sound. 2. The rime UYEN can be pronounced as WIN. Add the rime to the consonant cluster above (NG + WIN). 3. The E is actually accented in Vietnamese, á» (á»).