=MCONCAT(SI(B16:E16="x",B$14:E$14,"")," ")
=SUPPRESPACE(SI(B16="x",B$14,"")&" "&SI(C16="x",C$14,"")&" "&SI(D16="x",D$14,"")&" "&SI(E16="x",E$14,"")&" "&SI(F16="x",F$14,"")&" "&SI(G16="x",G$14,"")&" "&SI(H16="x",H$14,"")&" "&SI(I16="x",I$14,"")&" "&SI(J16="x",J$14,"")&" "&SI(K16="x",K$14,"")&" "&SI(L16="x",L$14,"")..............)
Function concat_tablo(myRange, delim As String)
concat_tablo = Join(myRange, delim)
End Function
=SUPPRESPACE(concat_tablo(SI(B16:E16="x",$B$14:$E$14,"")," "))