Pronunciation: [sˈʌdənliɪŋ] (IPA)
Correct spelling for the English word "suddenlying" is [sˈʌdənliɪŋ], [sˈʌdənliɪŋ], [s_ˈʌ_d_ə_n_l_i__ɪ_ŋ] (IPA phonetic alphabet).