Pronunciation: [θˈaŋksɪŋ] (IPA)
Correct spelling for the English word "thanksing" is [θˈaŋksɪŋ], [θˈaŋksɪŋ], [θ_ˈa_ŋ_k_s_ɪ_ŋ] (IPA phonetic alphabet).
Correct spelling for thanksing