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.
Children can encounter many different kinds of mistakes while learning to speak. Weâve all seen sitcoms or movies during which the younger sibling adorably mispronounces words, saying things such as âfrenâ instead of âfriend.â This type of mistake is actually called cluster reduction.