Hi Dyvia,

>ERROR [+2640]  TreeBuildCommand: TB commands must be in sequence

The TB command (used in the tree.hed script) clusters one specific set of states and is created with the mkclscript.prl command, and looks something like this:

TB 350 "ST_ae_2_" {("ae","*-ae+*","ae+*","*-ae").state[2]}
TB 350 "ST_b_2_" {("b","*-b+*","b+*","*-b").state[2]}

... 

Did you create your TB commands using mkclsript.prl command?: 

$perl ../HTK_scripts/mkclscript.prl TB 350 monophones0 >> tree.hed

Is your monophones0 file in sort order?   

Ken