diff --git a/src/fit.jl b/src/fit.jl
index ee081de..20d878e 100644
--- a/src/fit.jl
+++ b/src/fit.jl
@@ -77,7 +77,8 @@ end
 "element-wise trainer"
 trainepoch_E!(;inputs) = Dict(:colist => Vector{QTrees.CoItem}(), 
                             :queue => QTrees.thread_queue(),
-                            :pairlist => Vector{QTrees.CoItem}(),
+                            :itemlist => Vector{QTrees.CoItem}(),
+                            :pairlist => Vector{Tuple{Int, Int}}(),
                             :updated => Set{Int}(),
                             :spqtree => QTrees.hash_spacial_qtree(inputs))
 trainepoch_E!(s::Symbol) = get(Dict(:patient => 20, :nepoch => 2000), s, nothing)
@@ -101,7 +102,8 @@ end
 trainepoch_EM!(;inputs) = Dict(:colist => Vector{QTrees.CoItem}(), 
                             :queue => QTrees.thread_queue(), 
                             :memory => intlru(length(inputs)),
-                            :pairlist => Vector{QTrees.CoItem}(),
+                            :itemlist => Vector{QTrees.CoItem}(),
+                            :pairlist => Vector{Tuple{Int, Int}}(),
                             :updated => Set{Int}(),
                             :spqtree => QTrees.hash_spacial_qtree(inputs))
 trainepoch_EM!(s::Symbol) = get(Dict(:patient => 10, :nepoch => 1000), s, nothing)
@@ -212,11 +214,12 @@ end
 "dynamic trainer"
 trainepoch_D!(;inputs) = Dict(:colist => Vector{QTrees.CoItem}(), 
                             :queue => QTrees.thread_queue(),
-                            :pairlist => Vector{QTrees.CoItem}(),
+                            :itemlist => Vector{QTrees.CoItem}(),
+                            :pairlist => Vector{Tuple{Int, Int}}(),
                             :updated => QTrees.UpdatedSet(1:length(inputs)),
                             :loops => 10,
                             :spqtree => QTrees.linked_spacial_qtree(inputs), #fllowing 4 tiems: pre-allocating for dynamiccollisions
-                            :sptree2 => QTrees.hash_spacial_qtree(inputs),
+                            :sptqree2 => QTrees.hash_spacial_qtree(inputs),
                             :lbcollector => Vector{Int}(),
                             :treenodestack => Vector{QTrees.SpacialQTreeNode}())
 trainepoch_D!(s::Symbol) = get(Dict(:patient => 10, :nepoch => 2000), s, nothing)
diff --git a/src/qtree_functions.jl b/src/qtree_functions.jl
index 3495e55..45f8f87 100644
--- a/src/qtree_functions.jl
+++ b/src/qtree_functions.jl
@@ -96,9 +96,12 @@ function _totalcollisions_native(qtrees::AbstractVector, coitems::Vector{CoItem}
     colist
 end
 function _totalcollisions_native(qtrees::AbstractVector, 
-    labels::AbstractVector{<:Integer}=1:length(qtrees); kargs...)
+    labels::AbstractVector{<:Integer}=1:length(qtrees); 
+    pairlist::AbstractVector{Tuple{Int, Int}}=Vector{Tuple{Int, Int}}(), kargs...)
     l = length(labels)
-    _totalcollisions_native(qtrees, [@inbounds (labels[i], labels[j]) for i in 1:l for j in l:-1:i + 1]; kargs...)
+    empty!(pairlist)
+    append!(pairlist, (@inbounds (labels[i], labels[j]) for i in 1:l for j in l:-1:i + 1))
+    _totalcollisions_native(qtrees, pairlist; kargs...)
 end
 function _totalcollisions_native(qtrees::AbstractVector, labels::AbstractSet{<:Integer}; kargs...)
     _totalcollisions_native(qtrees, labels |> collect; kargs...)
@@ -155,15 +158,15 @@ function locate!(qts::AbstractVector, labels::Union{AbstractVector{Int},Abstract
     spqtree
 end
 
-function collisions_boundsfilter(qtrees, spindex, lowlabels, higlabels, pairlist, colist)
+function collisions_boundsfilter(qtrees, spindex, lowlabels, higlabels, itemlist, colist)
     for hlb in higlabels
         # check here because there are no bounds checking in _collision_randbfs
-        collisions_boundsfilter(qtrees, spindex, lowlabels, hlb, pairlist, colist)
+        collisions_boundsfilter(qtrees, spindex, lowlabels, hlb, itemlist, colist)
     end
 end
-function collisions_boundsfilter(qtrees, spindex, lowlabels, hlb::Int, pairlist, colist)
+function collisions_boundsfilter(qtrees, spindex, lowlabels, hlb::Int, itemlist, colist)
     if inkernelbounds(@inbounds(qtrees[hlb][spindex[1]]), spindex[2], spindex[3])
-        append!(pairlist, ((llb, hlb)=>spindex for llb in lowlabels))
+        append!(itemlist, ((llb, hlb)=>spindex for llb in lowlabels))
     elseif getdefault(@inbounds(qtrees[hlb][1])) == QTrees.FULL
         for llb in lowlabels
             if @inbounds(qtrees[llb][spindex]) != QTrees.EMPTY
@@ -173,22 +176,22 @@ function collisions_boundsfilter(qtrees, spindex, lowlabels, hlb::Int, pairlist,
         end
     end
 end
-function collisions_boundsfilter(qtrees, spindex, llb::Int, higlabels, pairlist, colist)
-    collisions_boundsfilter(qtrees, spindex, (llb,), higlabels, pairlist, colist)
+function collisions_boundsfilter(qtrees, spindex, llb::Int, higlabels, itemlist, colist)
+    collisions_boundsfilter(qtrees, spindex, (llb,), higlabels, itemlist, colist)
 end
 @assert collect(Iterators.product(1:2, 4:6))[1] == (1, 4)
 function totalcollisions_spacial(qtrees::AbstractVector, spqtree::HashSpacialQTree; 
-    colist=Vector{CoItem}(), pairlist::AbstractVector{CoItem}=Vector{CoItem}(), unique=true, kargs...)
+    colist=Vector{CoItem}(), itemlist::AbstractVector{CoItem}=Vector{CoItem}(), unique=true, kargs...)
     length(qtrees) > 1 || return colist
     nlevel = length(@inbounds qtrees[1])
-    empty!(pairlist)
+    empty!(itemlist)
     for spindex in keys(spqtree)
         labels = spqtree[spindex]
         labelslen = length(labels) 
         if labelslen > 1
             for i in 1:labelslen
                 for j in labelslen:-1:i+1
-                    push!(pairlist, (@inbounds labels[i], @inbounds labels[j]) => spindex)
+                    push!(itemlist, (@inbounds labels[i], @inbounds labels[j]) => spindex)
                 end
             end
         end
@@ -198,12 +201,12 @@ function totalcollisions_spacial(qtrees::AbstractVector, spqtree::HashSpacialQTr
             (@inbounds pspindex[1] > nlevel) && break
             if haskey(spqtree, pspindex)
                 plbs = spqtree[pspindex]
-                collisions_boundsfilter(qtrees, spindex, labels, plbs, pairlist, colist)
+                collisions_boundsfilter(qtrees, spindex, labels, plbs, itemlist, colist)
             end
         end
     end
-    # @show length(pairlist), length(colist)
-    r = _totalcollisions_native(qtrees, pairlist; colist=colist, kargs...)
+    # @show length(itemlist), length(colist)
+    r = _totalcollisions_native(qtrees, itemlist; colist=colist, kargs...)
     unique ? unique!(first, sort!(r)) : r
 end
 function totalcollisions_spacial(qtrees::AbstractVector{U8SQTree};
@@ -218,24 +221,25 @@ function totalcollisions_spacial(qtrees::AbstractVector{U8SQTree}, labels::Union
 end
 
 const SPACIAL_ENABLE_THRESHOLD = round(Int, 10+10log2(Threads.nthreads()))
-function totalcollisions_native_kw(qtrees, args...; pairlist=nothing, unique=true, spqtree=nothing, kargs...)
-    totalcollisions_native(qtrees, args...; kargs...)
+function totalcollisions_native_kw(args...; itemlist=nothing, unique=true, spqtree=nothing, kargs...)
+    totalcollisions_native(args...; kargs...)
 end
-function totalcollisions(qtrees::AbstractVector{U8SQTree}, args...; kargs...)
-    if length(qtrees) > SPACIAL_ENABLE_THRESHOLD
-        return totalcollisions_spacial(qtrees, args...; kargs...)
+totalcollisions_spacial_kw(args...; pairlist=nothing, kargs...) = totalcollisions_spacial(args...; kargs...)
+function totalcollisions(args...; kargs...)
+    if length(args[end]) > SPACIAL_ENABLE_THRESHOLD
+        return totalcollisions_spacial_kw(args...; kargs...)
     else
-        return totalcollisions_native_kw(qtrees, args...; kargs...)
+        return totalcollisions_native_kw(args...; kargs...)
     end
 end
 function partialcollisions(qtrees::AbstractVector,
     spqtree::LinkedSpacialQTree=linked_spacial_qtree(qtrees), 
     labels::AbstractSet{Int}=Set(1:length(qtrees)); 
-    colist=Vector{CoItem}(), pairlist::AbstractVector{CoItem}=Vector{CoItem}(),
+    colist=Vector{CoItem}(), itemlist::AbstractVector{CoItem}=Vector{CoItem}(),
     lbcollector = Vector{Int}(),
     treenodestack = Vector{SpacialQTreeNode}(),
     unique=true, kargs...)
-    empty!(pairlist)
+    empty!(itemlist)
     locate!(qtrees, labels, spqtree) #需要将labels中的label移动到链表首
     for label in labels
         # @show label
@@ -250,13 +254,13 @@ function partialcollisions(qtrees::AbstractVector,
             # 但要保证更prev的node在`labels`中
             treenode = seek_treenode(ln)
             spindex = spacial_index(treenode)
-            append!(pairlist, (((label, lb) => spindex) for lb in lbcollector))
+            append!(itemlist, (((label, lb) => spindex) for lb in lbcollector))
             tn = treenode
             while !isroot(tn)
                 tn = tn.parent #root不是哨兵，值需要遍历
                 if !isemptylabels(tn)
                     plbs = Iterators.filter(!in(labels), labelsof(tn)) #moved了的plb不加入，等候其向下遍历时加，避免重复
-                    collisions_boundsfilter(qtrees, spindex, label, plbs, pairlist, colist)
+                    collisions_boundsfilter(qtrees, spindex, label, plbs, itemlist, colist)
                 end
             end
             empty!(treenodestack)
@@ -271,13 +275,13 @@ function partialcollisions(qtrees::AbstractVector,
                     cspindex = spacial_index(tn)
                     clbs = labelsof(tn)
                     # @show cspindex clbs
-                    collisions_boundsfilter(qtrees, cspindex, clbs, label, pairlist, colist)
+                    collisions_boundsfilter(qtrees, cspindex, clbs, label, itemlist, colist)
                 end
                 for c in tn.children
                     if !isemptychild(tn, c) #如果isemptychild则该child无意义
                         emptyflag = false
                         push!(treenodestack, c)
-                        # @show pairlist
+                        # @show itemlist
                     end
                 end
                 emptyflag && remove_tree_node(spqtree, tn)
@@ -285,8 +289,8 @@ function partialcollisions(qtrees::AbstractVector,
         end
     end
     empty!(labels)
-    # @show length(pairlist), length(colist)
-    r = _totalcollisions_native(qtrees, pairlist; colist=colist, kargs...)
+    # @show length(itemlist), length(colist)
+    r = _totalcollisions_native(qtrees, itemlist; colist=colist, kargs...)
     unique ? unique!(first, sort!(r)) : r
 end
 mutable struct UpdatedSet{T} <: AbstractSet{T}
@@ -305,11 +309,11 @@ Base.length(s::UpdatedSet) = length(s.set)
 Base.iterate(s::UpdatedSet, args...) = iterate(s.set, args...)
 Base.in(item, s::UpdatedSet) = in(item, s.set)
 Base.in(s::UpdatedSet) = in(s.set)
-function totalcollisions_kw(qtrees; sptree2=hash_spacial_qtree(qtrees), 
+function totalcollisions_kw(qtrees; sptqree2=hash_spacial_qtree(qtrees), 
     spqtree=nothing, lbcollector=nothing, treenodestack=nothing, kargs...)
-    totalcollisions(qtrees; spqtree=sptree2, kargs...)
+    totalcollisions(qtrees; spqtree=sptqree2, kargs...)
 end
-partialcollisions_kw(qtrees, spqtree, updated; sptree2=nothing, kargs...) = partialcollisions(qtrees, spqtree, updated; kargs...)
+partialcollisions_kw(qtrees, spqtree, updated; sptqree2=nothing, pairlist=nothing, kargs...) = partialcollisions(qtrees, spqtree, updated; kargs...)
 function dynamiccollisions(qtrees::AbstractVector,
     spqtree::LinkedSpacialQTree=linked_spacial_qtree(qtrees), 
     updated::UpdatedSet{Int}=UpdatedSet(1:length(qtrees));